SCIENCE IN TENNIS
Journal of the STMS, the ITF, the ATP and the WTA Tour
In this issue:
4 MEET THE EXPERT: DR. BERNARD MONTALVAN
5 ULNAR SIDED WRIST PAIN
6 ABDOMINAL INTERNAL OBLIQUE MUSCLE
INJURY IN A TENNIS PLAYER
8 ENERGY BALANCE MONITORING IN
10 ON THE PROBABILITY OF WINNING A
12 SCORING TO REMOVE LONG MATCHES,
INCREASE TOURNAMENT FAIRNESS AND
14 LETTER TO THE EDITOR AND
REPLY TO LETTER TO THE EDITOR
16 INTERNATIONAL COMPARISON OF
18 CONFERENCE CALENDAR
20 SELECTED REVIEW OF THE LITERATURE
22 STRETCHING RECOMMENDATIONS FOR TENNIS
23 VISCOSUPPLEMENTATION NOT EFFECTIVE FOR
THE TREATMENT OF POSTTRAUMATIC
OSTEOARTHRITIS OF THE ELBOW
24 WTA TOUR AGE ELIGIBILITY AND
PROFESSIONAL DEVELOPMENT TEN YEAR
3 3RD ARGENTINE SYMPOSIUM OF SPORTS
MEDICINE APPLIED TO TENNIS
3 STMS HILTON HEAD MEETING
18 13TH ITF WORLDWIDE COACHES WORKSHOP
EDITORIAL Medicine and Science in Tennis is a Journal produced by the Society
for Tennis Medicine (STMS) in co-operation with the ITF, the ATP, and
the WTA Tour, and is issued three times a year (April, August, and
December). The STMS is an international organization of sports
medicine and science experts aiming to serve as an international forum
Dear tennis friends, for the generation and dissemination of knowledge of tennis medicine
THE INTERNATIONAL BOARD OF THE STMS
The end of the year is a good time to look back and reflect on President:
Babette M. Pluim, Arnhem,The Netherlands.
all that has happened in the preceding year. I would like to use Vice President:
Marc R. Safran, San Francisco,CA,USA;
this opportunity to look back at the activities of the STMS and Secretary:
Javier Maquirriain, Buenos Aires, Argentina;
of the main governing bodies in tennis (ATP, WTA Tour and E-mail: email@example.com
ITF) in the field of medicine and science. My main conclusion is Alan Pearce, Melbourne, Australia;
that everyone has been very active! Treasurer:
George C.Branche III, Arlington, VA, USA;
The WTA Tour has commenced a ten-year review of the Age Past-president:
Per A.F.H. Renström, Stockholm, Sweden;
Eligibility Rule and the Professional Development Department Other members:
Peter Jokl, New Haven, CT, USA;
programs. Experts met during the WTA Tour’s end-of-season W. Ben Kibler, Lexington, KY, USA.
Savio L-Y Woo, Pittsburgh, PA, USA
championships in Los Angeles to discuss the set-up of this Associates to the Board:
Miguel Crespo, Representative of the ITF;
proposed review (for more details, see page 24). WTA Primary Health Care providers Kathy Martin, Representative of the WTA Tour;
Gary Windler, Representative of the ATP.
Cathy Ortega and Laura Eby spoke at the Tennis Teachers’ Conference during the US
North American Regional Committee:
Open, on athletic shoes and equipment, and Cathy Ortega presented at the ITF Chairman: Marc R. Safran, San Francisco, CA, USA;
Peter Jokl, New Haven, CT, USA;
Worldwide Coaches’ Workshop in Portugal, on the importance of core stability for W. Ben Kibler, Lexington, KY, USA;
Michael F. Bergeron, Augusta, GA;
tennis. The WTA and ATP had some joint activities, including the 2003 Coach William Micheo, San Juan, Puerto Rico;
Carol L. Otis, Los Angeles, CA, USA;
Registration Symposium held at the US Open, and the ‘Evening with the Pros’ held E. Paul Roetert, Key Biscayne, FL, USA;
Savio L-Y. Woo, Pittsburgh, PA, USA.
during Wimbledon to introduce the juniors to professional tennis.
EUROPEAN REGIONAL COMMITTEE
Paul Settles will be seeking new opportunities outside the ATP as the head coach at Chairman: Giovanni di Giacomo, Rome,Italy,Chairman;
Gilles Daubinet, Paris,France;
the Claremont College in California. I would like to use this opportunity to thank Paul Hartmut Krahl, München,Germany;
Hans-Gerd Pieper, Essen,Germany;
for all his enthusiasm and hard work for the STMS and the ATP Tournament Babette Pluim, Arnhem,the Netherlands;
Angel Ruiz-Cotorro, Barcelona, Spain;
Physicians, many of whom are members of the STMS. Per Bastholt has been appoint- Michael Turner, London,United Kingdom;
Reinhard Weinstabl, Vienna, Austria.
ed as the new Director of Medical Services for the ATP.
SOUTH AMERICAN REGIONAL COMMITTEE
The ATP had several cases of positive doping tests for nandrolone. Anti-doping Chairman: Rogério Teixeira Silva, São Paulo,Brazil;
Javier Maquirriain, Buenos Aires, Argentina.
experts are looking into the possibility that these positive tests may have been the
result of supplement contamination which has become a significant problem in inter- Chairman: W. Ben Kibler, Lexington, KY, USA;
Michael F. Bergeron, Augusta,GA,USA;
national sports due to lack of regulation of the supplement industry. Bruce Elliott, Perth, Australia;
Karl Weber, Cologne, Germany;
Among the many activities of the ITF in the sports medical and science field I would Savio L-Y. Woo, Pittsburgh, PA, USA.
like to highlight the publication of the books ‘Strength and Conditioning for Tennis’ EDUCATIONAL COMMITTEE
and ‘Biomechanics of Advanced Tennis’, as well as the release of seven ‘Injury Cards’. Chairman: Marc. R. Safran, San Francisco, CA, Chairman;
George C.Branche III, Arlington, VA, USA;
The ITF also organised its 13th ITF Worldwide Congress in Portugal, on the theme of Henrik Ekersund, Gothenburgh, Sweden;
Stacie Grossfeld, Louisville, KY,USA;
Applied Sports Science for High Performance Tennis (see page 18). By inviting several Peter Jokl, New Haven, CT, USA;
W. Ben Kibler, Lexington, KY, USA;
scientists and medical specialists to make presentations at this congress, the ITF made Kathy Martin, Melbourne, Australia;
Fernando Segal, Buenos Aires, Argentina;
an excellent job of enhancing communication and building bridges between tennis Piotr Unierzyski, Poznan, Poland;
Gary Windler, Summerville, SC, USA.
coaches and tennis scientists. Editorial Board:
The STMS organised two meeting in 2003, one in Paris and one in Hilton Head Editor-in-Chief: Babette M. Pluim;
Jackie Bailey, Den Haag, The Netherlands;
(see page 3). The Board of the STMS met on both occasions. One of the decisions Todd Ellenbecker, Scottsdale, AZ, USA;
Javier Maquirriain, Buenos Aires, Argentina;
made was to hold annual instead of biannual world congresses. The 2005 STMS World Rogério Teixeira Silva, São Paulo,Brazil
Alan Pearce, Melbourne, Australia;
Congress will be hosted by Marc Safran in Indian Wells. An STMS educational Gary Windler, Summerville, SC, USA;
committee was founded, in order to improve our ability to realise our educational EDITORIAL OFFICE:
PO Box 302, 6800 AH Arnhem,
aims. The Netherlands.
During the ITF Worldwide Coaches Workshop in Portugal, we took the opportunity Fax +31-26-4834439
to organise a meeting between members of the STMS and several national tennis MEMBERSHIP OFFICE:
coaches, and to discuss the aims and educational program of the STMS. It was Alan Pearce, Ph.D.
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suggested that coaches may have a different view from doctors of the areas of tennis Private Bag 6060
that need research, so a survey among the 300 coaches was conducted to find out. And Victoria 3121
I have to admit: the participants were right! The main research focus of the STMS is T + 61 3 9286 1177
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epidemiology of injuries and heat stress, whereas the top five of topics that tennis E-mail: firstname.lastname@example.org
coaches are most interested in are recovery, speed training, injury prevention, burnout Full membership: $100.00
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and the psychology of optimal performance. Since it is very important to use this type Student membership $ 35.00
of information in the future endeavours of the STMS, several coaches were invited to MEMBERSHIP PAYMENTS:
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participate in the educational committee. Richmond 242 Bridge Road
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All in all, it has been an exciting and busy year, and I am particularly pleased to see Australia
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how increased co-operation within the tennis world is leading not only to higher Account # 10287882
quality research and education, but also to a greater motivation and interest among all PHOTOGRAPHERS:
Henk Koster, Arjan Verbruggen
those involved. I hope we can continue enhancing this positive working relationship, FRONT COVER:
and I would like to wish everyone a happy, healthy and stimulating 2004. LeAnn Silva, ATP, Ponte Vedra Beach, Fl, USA
Babette Pluim PUBLISHING OFFICE:
Modern BV, Bennekom, The Netherlands
President STMS WEBMASTER:
Ivo Wildeman, Hilversum, The Netherlands
The newsletter ‘Medicine & Science in Tennis’ is supported by: Disclaimer:
This journal is published by the Society of Tennis Medicine and
Science for general information only. Publication of information in the
journal does not constitute a representation or warranty that the
information has been approved or tested by the STMS or that it is
suitable for general or particular use. Readers should not relay on any
information in the journal and competent advice should be obtained
about its suitability for any particular application.
© 2003 Society of Tennis Medicine and Science. All rights reserved.
No part of this publication may be reproduced in any form without
prior written permission of the copyright holder. Opinions and research
expressed in this journal are not necessarily those of the STMS.
MEDICINE & SCIENCE IN TENNIS 2
3rd Argentine Symposium of Sports Medicine Applied to Tennis:
Current Concepts in Tennis Player Medical Care
Opening lecture by Jorge Franchella (FACSM) Alberto Osete, physical trainer of elite Speakers at the Argentine Symposium:
consultant of the AAT. Argentine players (including Gabriela F. Segal, C. Pena, J.M Flores, A. Osete,
Sabatini, Guillermo Coria, Gastón Gaudio A. Kokalj and J. Mazzucco (from left to right).
he 3rd Argentine Symposium of Sports and David Nalbandian) was presented with a
T Medicine Applied to Tennis was held in
Buenos Aires on 13 August 2003. The sci-
diploma by Javier Maquirriain (Medical
Director of AAT). Martin Sammartino (Hand Surgeon),
entific meeting was organised by the Fernando Segal (ITF Marketing Group),
Argentine Tennis Association and sponsored tional Requirements of Tennis’. Before the Juan Mazzucco (MRI expert) and Prof.
by the South American Tennis Confeder- afternoon break, Lic. José Luis Echegaray Alberto Osete (Davis Cup Trainer).
ation (COSAT). presented an interesting talk about ‘Tennis Professor Alberto Osete was honoured
Racquets: past, present and future’. with the award ‘Relevant Action in Sports
One hundred and eighty five participants The second part of the Symposium began Science – 2003’ for his contribution on
attended the Elevage Hotel to exchange with a keynote lecture on ‘Current Pattern tennis players´ development in the last
ideas and learn about ‘Current Concepts of Injuries in Elite Tennis Players’ by Dr. decade.
in Tennis Player Medical Care’. Javier Maquirriain, Medical Director of Sponsorship: the Symposium was support-
Dr. Jorge Franchella opened the Sympo- Argentine Tennis Association. ed by Laboratorio Temis Lostalo.
sium with a lecture on ‘Physiological The final session was an Open Forum Abstracts of the presentation will be avail-
Issues in Tennis’. Juan M. Flores then pre- Discussion on ‘How to support Argentine able in Spanish at
sented an update on ‘Strength training for Success in Tennis?’. Panellists included email@example.com,
Competitive Tennis’ followed by Lic. Carlos Pena (International Coach), Tony firstname.lastname@example.org and
María Mazzei, who lectured on ‘Nutri- Kokalj (Davis Cup Physiotherapist), www.temislostalo.com.ar.
STMS HILTON HEAD MEETING
he 9th North American meeting of the
T Society for Tennis Medicine and Science
was held at the Crowne Plaza Resort in
all three planes of motion. Kathleen Stroia
presented the WTA protocol for core stabi-
more and better, as the result of better con-
ditioning, more interest, and better medical
lization. care, including joint replacement. It was dis-
Hilton Head, SC on September 12- 14, Shoulder kinematics. Dr Glenn Fleisig pre- covered that the medical community
2003. Many interesting presentations were sented data from the 2000 Olympics regard- appears to be much more conservative than
given on a variety of tennis related topics. ing forces and loads on the shoulder and the players desire about playing with joint
The level of presentation and the discussion elbow during the tennis serve. The absolute replacement, and there does not appear to
was high, and all who attended felt the and relative values of the forces were high at be a significantly higher risk of complication
meeting was a scientific success. both joints, indicating a high rate of strain with more vigorous play.
during these motions. The role of proper Injury prevention. A symposium and work-
Flexibility. Dr Duane Knudson presented mechanics was emphasized by showing that shop highlighted problems and proposed
research showing that there is a difference lack of knee flexion (less than 10 degrees) in solutions. Dr Babette Pluim presented a
between static (how far the muscle/joint cocking was associated with a 15-23% framework for education and exercises that
complex can be moved) and dynamic (the increase in loads at the shoulder and elbow. has been developed by the Royal
rate of strain, or the stiffness) flexibility. Glenohumeral internal rotation deficit Netherlands Lawn Tennis Association to
Each component appears to be important (GIRD). Dr Ben Kibler presented data decrease injuries. There was a lengthy dis-
for performance and injury risk reduction. regarding the acquired loss of internal rota- cussion on the best methods to implement
Dynamic flexibility exercises should be done tion seen in overhead athletes including ten- the best strategies for different populations-
immediately before play, while static flexi- nis players. The deficit creates abnormal youth, adults, and professionals.
bility exercises are best done in between motions of the glenohumeral joint in all The social part of the meeting was high-
bouts of exercise (see page 22 for the full phases of the serve. In cocking, the humerus lighted by two days of high level tennis.
article). moves posterior/superiorly on the glenoid, Dennis van der Meer and his teaching pro-
Core Stability. Dr Joel Press presented the in follow through, the humerus moves ante- fessionals led a vigorous and entertaining
basic science rationale, evaluation process, rior/superiorly. These abnormal motions are clinic on one day, and then we put all the
and rehabilitation techniques for improving thought to be the primary alteration that teaching into practice the following day.
core stability to improve movement, speed, leads to labral tears and partial rotator cuff Evening activities included a patio cookout
and power, and decrease injury risk. Loss of tears. and reception.
core stability was shown to be a factor in Older tennis players. Dr George Branche and The Board, in its session, decided that the
ability to run, stop, plant, and swing. The Dr Peter Jokl presented data that showed next North American meeting will be held
emphasis was on motion and evaluation in older tennis players can be expected to play in Palm Desert, CA in 2005.
MEDICINE & SCIENCE IN TENNIS 3
MEET THE EXPERT:
Dr. Bernard Montalvan, Medical Director of the French Open
defined all the time, and the therapeu-
tic options are being coded better. I
congratulate Babette Pluim and all of
her staff for the work they have done,
which has helped us to progress, with-
out forgetting the medical teams of the
WTA and ATP. Finally, the contacts I
have been able to maintain with other
experts such as Brian Hainline, Medical
Director of the US Open, and Angel
Cotorro, the doctor from the Spanish
delegation, are always enriching. Of
course we have introduced measures for
occasional heat stress conditions – these
are very good measures.
From a practical point of view, we have
defined the emergency procedures that
offer our players the best possible care
in case there is an urgent problem.
8 Is there a difference in the medical
care of male and female athletes?
Bernard Montalvan and Jacques Parier The women have become more and
more athletic and in this sense, the
r. Bernard Montalvan is Medical nal medicine) at the Ambroise Pare women’s game is now catching up with
D Director of the Roland Garros tour-
nament and also works for the French
public hospital. the men’s game. There is no clear dif-
ference in terms of traumatology,
Tennis Federation. In a long and distin- 4 Which tournaments do you cover? except for the hormonal phenomenon.
guished medical career, he has played a In addition to Roland Garros I also We may not yet understand all the
key role in developing medical services cover the Paris BNP Bercy tournament, effects of this on women.
for tournament tennis players in France. which is held in November.
Here he reviews some of the highlights of 9 What is the most interesting medical
his career – including the salutory lesson 5 How did you first become involved problem you have encountered?
that even the best physicians can some- in providing medical cover for tennis I remember an amusing story. On the
times get the wrong end of the stick ! tournaments? first day of the tournament, the match-
I started working with Jean Pierre es start at 11.00 a.m. I was called onto
1 What is your specialty? Cousteau at the FFT. We made progress the court at 11.20, for a player who felt
I am rheumatologist with a degree in together and when he left, which I very tired and nauseated after only two
sports medicine and in tramatology and much regretted, it was quite natural change-overs. He looked very pale and
sport. that I became his sucessor. sweaty. The clinical examination was
normal, so we told him to drink water
2 For how long have you worked as a 6 Are you responsible for the general and take the time to catch his breath in
tournament doctor? public as well? between the rallies. Finally he won and
I started working for the French Open During the Roland Garros tournament, slept all afternoon in the sickbay, snor-
in 1986, with Dr. Jean-Pierre Cousteau. an independent medical service is ing loudly. The medical tests were all
We developed the medical service espe- responsible for the general public. We normal, except for his nausea. The
cially for our players in 1985. Dr. are only involved with the players. If blood tests showed a rise in his SGOT
Cousteau retired in 2000, after which I there is a serious medical problem that and SGPT levels (liver enzymes). They
took over his position as Medical requires urgent resuscitation or other were about twice as high as normal. We
Director of the Roland Garros tourna- intervention, the two medical teams were therefore considering the possibili-
ment. I would like to mention two doc- work together. ty of the onset of liver disease and so
tors who have proved to be indispensa- on . . . and told the player it would be
ble to the effectiveness of the medical 7 What changes have you made over very difficult for him to finish the tour-
service: Dr. Jacques Parier, sports physi- the years that have had the greatest nament. But finally his coach appeared
can, and Dr. Jean Louis Brasseur, positive impact on care for players at (late that evening, at 10.00 p.m.) and
echographist. It is a real pleasure to tournaments? admitted to us that the evening before,
work with them. From a general point of view, we have the player had been really drunk and
made progress by taking the demands of that we should wait with our diagnosis.
3 What is your regular job? the players into account. We can now In two days, all the blood tests had nor-
I work part-time for the French Tennis give them appropriate and high-quality malised and the player felt as good as
Federation (FTF), I have a private prac- care within a short time-span (24 new. We should not forget that the
tice and I have a post in the clinic of hours). The specific pathologies of the players are mischievous boys – and
Prof. Le Parc (rheumatology and inter- tennis player are becoming better most are only around twenty years old!
SPORTS MEDICINE & SCIENCE IN TENNIS 4
LE Ulnar Sided Wrist Pain
ANGEL RUIZ-COTORRO1,2, MD, JAUME VILARÓ2, MD AND STEPHEN UMANSKY3, MD.
1 Real Federación Española de Tenis, Federación Catalana de Tenis; 2 Clinica Fundació FIATC, Avda Diagonal 648, 08017 Barcelona, Spain
3 Lexington Clinic Sports Medicine Centre, 1221 South Broadway, Lexington, KY, USA
U lnar sided wrist pain is characterized by
pain on the ulnar border of the wrist and
can be divided into degenerative or acute
ABOUT THE AUTHORS
Dr Angel Ruiz-Cotorro is sports physician
and medical director of the Spanish Tennis
processes. The likely syndromes to affect ten-
Federation and the Catalan Tennis
nis players are ulnocarpal impaction syn- Federation. He is the team physician of their
drome (degenerative) or triangular fibrocarti- Davis Cup and Fed Cup teams and has a
lage complex (TFCC) tear (acute). position at the FIATC Clinic in Barcelona.
Anatomy Dr. Jaume Vilaró is orthopedic surgeon at
The ulnocarpal joint space is bounded by the the FIATC Clinic and has a special interest in
lunate, lunatotriquetral ligament, and tri- tennis.
quetrum superiorly, and the triangular fibro-
cartilage covering the ulnar seat and distal Dr Steve Umansky is an orthopedic surgeon
radio-ulnar joint inferiorly (Figure 1). The and chief of the Hand Surgery service at the
disc-carpal ligaments (disc-lunate and disc- Figure 2 The articular disc Lexington Clinic in Lexington, KY. He did his
triquetral) form the volar border, and the cap- residency at the University of Pennsylvania
sule confluent with the extensor carpi ulnaris and his hand fellowship at the Indiana Hand
tendon sheath forms the dorsal border. The ing micro or macro instability to the distal Center in Indianapolis, IN. His special inter-
radial border is the sigmoid fossa of the distal radio-ulnar complex. ests are in wrist fractures and ulnar sided
radius. wrist pain in athletes.
In the ulna-positive individual, chronic
The articular disc or meniscal homologus is a impaction between the lunate, lunato-trique-
fibrocartilagenous structure that forms a sling tral ligament, or triquetrum with the promi- help with symptoms. Rehabilitation and pro-
between the dorsal and palmar radio-ulnar nent head of the ulna or styloid can cause gressive return to prior level of competition
ligaments which has a broad attachment to chronic degeneration of the interposed TFCC should be supervised by a hand therapist.
the sigmoid notch of the radius and inserts and/or the cartilage surfaces that are subject- If conservative management fails to get the
along the ligaments to their insertions at the ed to abnormal load, point stresses, and shear. expected result, arthroscopic evaluation and
distal ulnar fovea and ulnar styloid (Figure 2). This occurs mainly during the rotation of an staging of the lesion should be undertaken. In
ulnar deviated wrist, or repetitive ulnar devia- some cases arthroscopic repairs or resection of
Predisposing factors tion. torn and unstable cartilage can be performed.
Anatomic factors predisposing injury of this Other cases require open reconstruction of
structure in a tennis player include ulna posi- Clinical features the wrist. Evaluation of other injuries and
tive variance or styloid magna. Specific to The main clinical features of the syndrome are: limited synovectomy can be performed at
tennis, the type of stroke and grip can predis- • Pain in the ‘foveal region’ just distal to the that time. Chondroplasty can also be per-
pose to injury. The forehand drive is the ulnar styloid. This may be elicited by pas- formed to smooth moving surfaces and
stroke that most frequently causes injury. sive pronation and supination of the wrist improve symptoms.
The two-handed backhand (non-dominant with the examining fingers palpating stress-
hand), the topspin (twist) serve and the fore- ing the distal radio-ulnar relationship. It
hand volley are also implicated. The Western- may also be elicited by passive ulnar devia-
like closed grip, predominantly adopted by tion of the wrist (TFCC grind test).
the Spanish and Argentinean clay court • Synovitis or inflammation may be present.
players, is without a doubt another principal • There is usually preserved motility of the
cause of the syndrome. distal radio-ulnar joint and wrist joint
• X-rays show no degenerative changes of the
Pathogenesis distal radio-ulnar joint.
When the wrist is extended and pronated, the
extensor carpi ulnaris tendon is relaxed. The Diagnosis
movement of the head of the ulna is therefore A detailed clinical history provides us with
not limited. Forced translation of the head of the most information. Standard neutral rota-
the ulna dorsally, or hyper-pronation or tion posteroanterior and lateral radiographs
provide information regarding the ulna vari- Figure 3 Pain may be elicited in the ‘foveal
hyper-supination may cause a tear of the region’ just distal to the ulnar styloid by passive
articular disc and/or the peripheral attach- ance and status of the bones (degenerative
pronation and supination of the wrist, with the
ment of the radio-ulnar ligaments. This can cysts or arthritis). Magnetic resonance
examining fingers palpating stressing the distal
cause pain from mechanical symptoms due to imagery is promising but imperfect and must radio-ulnar relationship.
the torn cartilage interposing between highly be correlated with a specific history and phys-
congruent surfaces during motion or by caus- ical examination. Bone scans can highlight
degenerative lesions of the lunate, triquetrum Conclusions
or distal ulna. Precisely placed lidocaine injec- Ulnar sided wrist pain can be classified as
tion tests can help localize the site of the either acute or chronic. Anatomic factors and
pathology to a specific region. swing and grip can predispose a player to
The differential diagnosis includes: Appropriate training can help decrease the
• Extensor carpi ulnaris subluxation risk of injury by correcting maladaptive
• Distal radio-ulnar joint instability or arthritis swinging technique. Appropriate diagnosis
• Fractures of the hook of the hamate rests on knowledge of the conditions and a
• Piso-triquetral arthritis complete history and physical examination,
• Flexor carpi ulnaris or Extensor carpi ulnaris sometimes including arthroscopic examina-
• Ulna styloid fracture Medical and surgical treatment is effective in
• Luno-triquetral ligament ruptures treating these complex lesions.
Acute cases of ulno-carpal impaction syn- 1. Garcia Elias M. Hand clinic 1998;14
drome or TFCC tears should be immobilized (2):165-176.
in a splint or case that prevents forearm rota- 2. Rettig AC. Wrist problems in the tennis
tion for a period of 4 to 6 weeks. Non- player. Med Sci Sports Exerc
Figure 1 The ulnocarpal space steroidal anti-inflammatory medication can 1994;26:1207-1212.
SPORTS MEDICINE & SCIENCE IN TENNIS 5
LE ‘Abdominal Internal Oblique Muscle Injury
in a Tennis Player’
JAVIER MAQUIRRIAIN, MD, PHD AND JUAN P. GHISI, MD, CENARD, ARGENTINE TENNIS ASSOCIATION. E-MAIL: JMAQUIRRIAIN@YAHOO.COM
Introduction showed a focal hyperintense area in the ABOUT THE AUTHORS:
The muscles of the anterolateral abdomi- proximal portion of the middle layer of
Javier Maquirriain, MD, PhD, is an
nal wall consist mainly of three broad, thin the lateral abdominal wall (Figure 1). orthopaedic surgeon working at CeNARD
layers that are aponeurotic in front: the (Argentine Olympic Centre). He is spe-
external oblique, the internal oblique, and Diagnosis of the left internal oblique strain cialised in sports injuries and arthroscopic
the transverses, from exterior to interior.6 muscle injury (grade 1) was established, surgery. He has published several articles
On both anterior sides of the midline, and the player was advised to avoid com- on ‘tendon endoscopic surgery’. He is
there is a wide vertical muscle, the rectus petition. Initial treatment consisted of rest, Medical Director of the Argentine Tennis
abdominis. The internal oblique muscles girdle compression, cryotherapy, oral anti- Association.
are located deeper than the external inflammatory medication and physical Juan Pablo Ghisi, MD is a radiologist work-
oblique ones. The internal oblique origi- modalities. Afterwards, isometric strength- ing at J.A. Fernandez Hospital, the largest
nates from the lumbar aponeurosis, the ening and static stretching was prescribed. medical centre in Buenos Aires. He is spe-
anterior portion of the iliac crest and the As the patient did not refer pain during cialised in MRI evaluation of musculo-
inguinal ligament. It inserts superiorly on those activities, he began concentric skeletal injuries. He is medical advisor of the
the 9th, 10th, 11th and, 12th costal cartilages strengthening exercises as well as aerobic Argentine Tennis Association.
on the linea alba, and is continuous with conditioning. The final stage of rehabilita-
the internal intercostal muscles. The inter- tion emphasised eccentric strengthening the upper limb. The abdominal obliques
nal oblique muscles are flexor and homo- and plyometric exercises. He returned to showed greater than 100% maximum
lateral axial rotators. They are innervated high-level competition in four weeks and manual test activity during the swing and
by the 8th to 12th intercostals nerves and he did not report recurrences in the fol- follow through phases. The sustained high
also by the abdominogenital nerve. lowing twelve months. muscle activity in the trunk muscles indi-
cates the relevance of back and abdominal
Several articles1,3 have been published Discussion stabilisation.
about abdominal anterolateral muscle The internal and external oblique muscles
trauma but, to the best of our knowledge, are examples of muscles that do not follow In the follow-through phase of the back-
there is no description of internal oblique a straight line between origin and inser- hand ground stroke, the trunk is decelerat-
indirect injury in the Sports Medicine lit- tion, but wrap around the torso. This ellip- ed. A high level of activity in the abdomi-
erature. tical model gives a mechanical advantage nal oblique muscles during that stage sug-
to oblique muscles, especially in axial rota- gests their eccentric role in decelerating
The purpose of this report is to describe an tion when the torso is flexed, extended or the trunk after the impact. The relatively
acute injury of the internal oblique twisted.4. Anatomic linkage between the low level of activity in the scapulohumeral
abdominal muscle in a professional tennis shoulder girdle and the abdominal muscu- muscles during batting indicates that the
player. lature has been demonstrated.2 emphasis for rehabilitation or training
should be placed on strengthening of the
Case Report Due to their anatomic location, the trunk and the hip muscles.
A 22-year old right-handed professional obliques can be considered as multiarticu-
tennis player presented with acute pain in lar muscles. As they link the torso and In summary, strain injuries of internal
the left anterolateral abdominal wall dur- pelvis structures, they are particularly oblique abdominal muscles are uncommon
ing a practice session. He referred sudden involved in sports actions. in the athletic population. They often
pain during an uncoordinated twisting result from extreme, unbalanced, eccentric
motion in a one-handed backhand stroke. Dynamic electromyographic analyses of muscle contractions (in the adolescent
He was immediately examined by the first abdominal muscles during tennis strokes injured athlete, avulsion iliac crest fracture
author, presenting mild discomfort, ten- have not been performed, but are expect- should be ruled out). In sports involving
derness close to the anterior arc of the 11th ed to be similar to that calculated for base- heavy trunk rotational motions, such as
and 12th ribs and pain on contraction- ball hittingbatting5. Such rotational athlet- tennis, special emphasis should be placed
against-resistance manoeuvres. Stretching ic movements are sequences of co-ordinat- oin hip and trunk strengthening.
the left lateral abdominal wall also elicited ed muscle activity, which begins in the
pain. Magnetic resonance imaging (MRI) hip, follows in the trunk and finishes in References
1 Balduini FC. Abdominal and groin
injuries in tennis. Clin Sports Med
B 2 DeRosa C. The morphology of the
abdominal muscles: implications of
function from structure. J Orthop
Sports Phys Ther 1999;29(1):A22.
3 Emery CA, Meeuwisse WH, Powell
JW. Groin and abdominal strain injuries
in the National Hockey League. Clin J
Sport Med. 1999;9(3):151-156.
4 Gatton M, Pearcy M, Peret G.
Modelling the line of action for the
oblique abdominal muscles during an
elliptical torso model. J Biomech
Figure 1 5 Shaffer B, Jobe FW, Pink M, et al.
A: Axial oblique MR image T2 weighted of left abdominal wall in a professional tennis player. There is a
focal abnormal signal intensity in the upper portion of the internal oblique muscle (arrow), compatible
Baseball batting. An electromyographic
with strain. The hyper-intensity area in the surrounding soft tissue represents perifascial oedema. study. Clin Orthop 1993;292:285-293.
B: Axial image T1 weighted of the same patient shows high signal intensity at the tear site, indicating 6 Snell RS. In: Gross Anatomy. Boston:
blood presence that characterizes the acute phase of muscular strain (arrowhead). Little, Brown and Company, 1990.
MEDICINE & SCIENCE IN TENNIS 6
Strength and Conditioning for Tennis
trength and Conditioning for Tennis is short of suggesting that a player’s schedule variety of techniques and exercises can be,
S one of the most comprehensive
resources currently available on the topic
may in fact limit the strength gains a
player might experience if there was an
and have been, used effectively to
of training players to be able to meet the ‘off-season’ in tennis. It is up to the coach to determine which
demands of today’s tennis game. Strength techniques are best suited for his/ her
and conditioning is a topic that has always One of the most beneficial aspects of players and design an appropriate strength
been important to all tennis players, yet ‘Strength and Conditioning for Tennis’ is and conditioning plan. ‘Strength and
historically it has been neglected for the that it incorporates information from a Conditioning for Tennis’ is a comprehen-
sake of additional ‘on-court’ training. variety of sources and a number of coun- sive resource that can assist any coach in
tries; the reader is often presented with doing this.
However, as the game has changed, we multiple views on a topic and how it
now see more and more players playing a should be approached. Scott Riewald, Sport Science Administrator,
faster and more powerful game. But has The ITF does not promote one ‘best way’ USTA
their training been adapted to prepare the to approach strength training and condi-
body for these increased demands? In tioning for tennis players, but rather pres-
many cases the answer is no, resulting in ents much of the available information STRENGTH AND CONDITIONING FOR TENNIS
injury and impaired performance. This pertaining to strength and conditioning Machar Reid, Ann Quinn and
book can serve as a guideline for anyone and discusses how it can lead to improved Miguel Crespo (eds)
who is looking to develop a tennis specific performance.
strength and conditioning program, from This fits with the idea that there is not one Number of pages: 272
the introductory coach who knows very way that is going to be best for every play- London: ITF 2003
little about the topic, to the advanced er, other than every player needs a ISBN 1 903013 19 4
strength and conditioning coach who is strength and conditioning plan if perform-
looking for new ideas. ance is going to be improved. A wide For orders please visit www.itftennis.com
The book begins with arguably the two
most important chapters, which deal
respectively with ‘Screening and Testing’
and ‘Athlete Development’. As highlight-
ed in the book, periodic testing is essential
to identify areas of weakness as well,
reveal any medical problems what would
impact how the player should be trained
as well as assess progress and strength
development. In looking at the long-term
development of a player it is important to
consider how strength and conditioning
can be used to optimize his/ her perform-
ance, not necessarily immediately, but
maybe several years down the road when
‘all the physical and mental pieces are in
A coach or trainer should be aware of how
a player develops, physically, emotionally
and psychologically, and then decide how
best to approach training based on the
athlete’s ‘maturity’. The remainder of the
book focuses on the different components
of a player’s game, like coordination,
power or agility, and how they can be
Finally the book concludes with several
chapters that deal with considerations to
take into account when dealing with
female, elderly, wheelchair, or professional
Throughout the entire text the concept of
periodization, or ‘cyclical training’ involv-
ing periods of work and rest, is touched
on. This is an important topic for discus-
sion since unlike most sports, tennis does
not have an off-season when players can
dedicate their efforts to building a strength
The authors present various ways for
working around this problem – providing
players an opportunity to build strength
without sacrificing playing time – but falls
MEDICINE & SCIENCE IN TENNIS 7
LE Energy Balance Monitoring in Tennis Players
BONITA L. MARKS, PHD, ELIZABETH GALLEHER BS, TERESA MOORE, PHD, LRD, AND
LAURENCE M. KATZ, MD. UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL, NC,
DEPARTMENT OF EXERCISE AND SPORT SCIENCE, USA. 27599-8700.
TEL: +1-919-962-2260 FAX: +1-919-962-0489 E-MAIL: MARKS@EMAIL.UNC.EDU
here is limited research regarding the movement and was based upon the sub-
T caloric needs of college tennis players.
Even though there are approximations for
ject’s personal characteristics programmed
into its memory. This is appropriate as
ABOUT THE AUTHOR:
Bonita L. Marks, PhD is an Associate
Professor of Exercise Physiology and
the energy cost of tennis match play, infor- resting metabolic rate generally accounts Director of the Exercise Science Teaching
mation is scant regarding total energy out- for 60-75% of one’s total daily caloric Laboratory at UNC’s Exercise and Sports
put which combines not only tennis prac- expenditure, with activity, exercise, and Science Dept. She also holds an adjunct
tice and conditioning, but also routine col- dietary thermogenesis plus other factors Associate Professor position in UNC’s
lege life. The ability to estimate energy making up the balance.8 The athlete School of Medicine. Bonita is a fellow of the
expenditure during physical activity with American College of Sports Medicine and
recorded the unit’s caloric output value in
an ACSM-certified Exercise Specialist. Her
reasonable accuracy is important in order a log prior to going to bed and upon wak- research interests are tennis, fitness/weight
to determine adequate caloric intake for ing in the morning. During the same week, management, and aging.
optimal performance. Estimating the ener- the athlete kept a daily log in which he
gy expenditure in a sport such as tennis is recorded all of his activities from rising to
complex because of the wide variety of going to bed. sponded to the same time intervals used in
movements performed during play. While Time spent in each activity as well as per- the activity logs (awake – noon, noon – 6
many studies have used Caltrac™ activity ceived intensity level were also recorded so pm, 6 pm – bedtime). Each athlete was
monitors (Figure 1) and self-reporting that caloric expenditures could be estimat- contacted periodically throughout the
mechanisms in the general population as ed using metabolic (MET) equivalents.9 week to ensure that the Caltrac™ device
well as in various sports,4-6 none have The calculation of caloric expenditure was being used properly as well as to rein-
reported use of the Caltrac™ nor self- required the researcher to code the activi- force accurate self-reporting. At the end of
reports to determine energy balance in col- ties according to the reported intensity the week-long recording period, the logs
lege-level competitive tennis players. The level (Table 1). were privately reviewed with each player
study of energy balance (caloric intake vs. to clarify reports.
caloric expenditure) could assist with per- Table 1 Metabolic Coding Table9
formance enhancement. Results
Thus the purpose of this study was to Activity MET Assignment Eight of the 11 tennis players completed
compare energy balance for a typical week Description the study. One failed to complete the
of activity, including energy intake and Sleep 1 MET daily recalls and two others did not wear
energy expenditure via self reports vs. Light 1.5 METs their Caltrac‘ units consistently. The
Caltrac activity recordings in male college Moderate 4 METs team’s descriptive characteristics were as
tennis players. Hard 6 METs follows (mean ± SD):
Very Hard 10 METs age: 20.3 ± 1.8 years, weight: 77.5 ± 7.4 kg,
Methods height: 180.6 ± 4.6 cm, estimated body fat
Subjects: Eleven college men from a U.S. The assigned MET value was then multi- (skinfolds): 8.2 ± 3.5%,
NCAA Division-I team were invited to plied by the amount of time spent in each VO2max: 61.0 ± 4.5 ml•kg-1•min-1.
participate in this research. At the time of activity, with the sum of the 24-hour
the study, the team was ranked in the top METs/hr adjusted for the subject’s body The caloric outputs obtained during the
25 by the ITA. All were healthy and mass, thereby resulting in a daily kilocalo- case-study comparison of the COSMED®
between 18-23 years of age. During an rie expenditure value.9 For example, if a versus the Caltrac™ yielded almost identi-
hour-long meeting, the players were given 75 kg player reported practicing for two cal results (COSMED®: 7.75 kcal•min-1
detailed instructions (both verbal and writ- hours at a moderate intensity, the calcula- versus Caltrac™: 7.70 kcal•min-1).
ten) regarding the appropriate use of the tion would be: Furthermore, statistical analysis (repeated
Caltrac™ device as well as for dietary 75 kg x 2 hrs x 4 METS = 600 kcal measures with planned contrasts) of the
intake and physical activity recording pro- (where 1 MET 1 kcal•kg-1•hr-1). case study subject found no significant
cedures. differences between the week-long
One player also participated as a case Concurrent with activity monitoring, the Caltrac™ monitoring and the self-reported
study pilot which compared the caloric athlete kept a daily food log in which he data (Caltrac = 3327 + 346 kcal•day-1 vs.
output between a COSMED® portable recorded everything he ate or drank for activity log = 3315 + 303 kcal•day-1 vs.
metabolic gas measurement unit to the the entire day. The dietary reports corre- dietary intake = 3433 + 613 kcal•day-1,
Caltrac™ for 30 minutes during a practice p > 0.721). However the initial success
hitting session (Figure 2). This case study with this one individual did not carry over
subject agreed to wear two Caltracs™ for to the team study population.
operational comparisons during an exhibi-
tion match. Similar analyses for the team data showed
that the Caltrac‘ caloric output reports
Instrumentation: At the beginning of (3821.4 ± 593.5 kcal•day-1) were signifi-
Day 1, a specific Caltrac™ device was pro- cantly higher (p < 0.04) than either of the
grammed with the subject’s age, weight, self-reports for physical activity (3142.4 ±
height, and gender. It was attached to the 299.1 kcal•day-1) or dietary intake (3082.0
waistband on the athlete’s non-dominant ± 594.4 kcal•day-1). The self-reports were
side. The unit was worn continuously for not significantly different from each other
the remaining six days unless sleeping, (p = 0.74).
bathing, or swimming (and none reported
During non-wearing times, the Caltrac™ Under-reporting is a common problem
continued caloric counting utilizing a rest- when self-reports of physical activity and
ing metabolic formula for energy expendi- food intake have been utilized, especially
ture which assumed little meaningful Figure 1 The Caltrac™ accelerometer device in female overweight populations.1 In this
MEDICINE & SCIENCE IN TENNIS 8
study, errors in self-reporting were likely expanded future study should be done to
reduced due to rigorous individual follow- validate the Caltrac™ output, testing the
up with the players as well as the subject various alternate modes under a variety of
population being lean athletic males. As tennis play conditions. In addition, weekly
such, the self-report recalls were in agree- weight monitoring would also be useful
ment, suggesting that the tennis players for cross-validating. While weigh-ins are
were eating enough calories to meet their routine in sports such as football and
energy demands. wrestling for dehydration prevention, this
On the other hand, the Caltrac™ device has not been done in any systematic fash-
has been shown to both over- and under- ion with tennis.
estimate caloric expenditure, depending
upon the nature of the activities being The probable overestimation of caloric
monitored.3 The daily Caltrac™ caloric output with week-long Caltrac™ monitor-
outputs measured in this study were 679 ing as seen in this study may be inherent in
calories higher than the activity self- the device’s internal mathematical compu-
reports and 739 calories higher than the tations or it could have been due to inad-
reported daily caloric intake. vertent user error. Nevertheless, the
Caltrac™ units are small, do not interfere
If this outcome were true, then it would with tennis mechanics, are less time con-
have been expected that the players would suming for recording purposes, and are
have experience lost approximately 0.5 kg fairly affordable (about 70 US$) in com-
monthly. Anecdotal reports suggested that parison to other more sophisticated meas-
these players tended to lose about 2.5 kg urement devices. Therefore, they are
from pre-season (September) to post-col- attractive units to use for energy balance
legiate season (May). Although we were determination.
not able to monitor the players for this
extended time period, it was estimated However, until the Caltrac™ device can
that if the Caltrac™ output data were be proven to provide more accurate meas-
true, a total weight loss of 4.5 kg would ures of caloric output under tennis training
have been expected for the 9 month peri- conditions as well as daily living, it is sug-
od. That would equate to almost twice the gested that the traditional self-report logs
amount of weight loss reportedly seen. with follow-up checks continue to be used
Hence it appears that the Caltrac™ device Figure 2 Case-study subject waiting a ten- for assessing energy balance in tennis
overestimated the players’ energy expendi- nis ball while fitted with the COSMED® players.
tures in this study. portable metabolic gas measurement device.
The Caltrac™ has been shown to be a 1 Ballew C and Killingsworth RE. Esti-
relatively accurate device to estimate body mass movement (such as with mation of food and nutrient intakes of
caloric expenditure in a two-dimension cycling or weightlifting), then an alternate athletes. In: Driskell JA and Wolinsky I
plane of movement5 as well as in a game- mode should be utilized for the duration (eds). Nutritional assessment of
sport such as basketball.2 During the bas- of the alternate activity. The ‘pedal’ mode athletes. Boca Raton:CRC Press 2002:
ketball study (n = 10), caloric output for is to be used not only during cycling, but 7-42.
30 minutes of simulated play (running, also when weightlifting with short rest 2 Ballor D, Burke L, Knudson D, Olson J,
walking, jumping, dribbling, passing, periods (< 1.5 minutes rest between sets). Montoy H. Comparison of three meth-
blocking) was measured with a Parkinson- The additional modes incorporate correc- ods of estimating energy expenditure:
Cowan gasometer and on a separate occa- tion factors to the metabolic formula in Caltrac, heart rate, and video analysis.
sion, 37 minutes of actual game play was order to prevent the under-estimations Res Quart Exerc Sport 1989;60:
monitored with a Caltrac™ unit. The that were reported in the earlier 362-368.
caloric outputs were similar with expired literature.7 Our case study subject had also 3 Bassett D. Validity and reliability issues
gas analyses measured during simulated worn two Caltracs™ while competing in in objective monitoring of physical
play resulting in 6.2 kcal•min-1 vs. 5.8 an exhibition match, with one set on activity. Res Quart Exerc Sport 2000;
kcal•min-1 as recorded by the Caltrac™ ‘regular’ mode and the other set on ‘pedal’ 71:21-29.
(p > 0.05). mode. 4 Kriska A, and Casperson C. A collection
While these caloric expenditures are lower of physical activity questionnaires for
than what we measured with our case The ‘pedal’ mode nearly doubled his healthy- related research. Med Sci
study tennis player, it is the only published caloric output (8.3 vs. 16.3 kcal•min-1, Sports Exerc 1997:29:S1-S205.
study that attempted to determine the ‘regular’ vs. ‘pedal’ modes, respectively). 5 Miller D, Freedson P, Kline G.
validity of using the Caltrac‘™ for energy Hence, we were very clear in our instruc- Comparison of activity levels using the
monitoring during an intermittent-type tions to the team to be extremely careful Caltrac accelerometer and five ques-
sport with a variety of movement when utilizing the various modes of the tionnaires. Med Sci Sports Exerc
patterns. Caltrac™ device. Although no player 1994;26:3376-382.
admitted to misusing the device, it is pos- 6 Montoye H, Kemper H, Saris W,
A more recent report by Bassett concluded sible that some did not immediately return Washburn R. Measuring physical activ-
that the Caltrac‘ may overestimate the their unit of operation back to ‘regular ity and energy expenditure. Champaign:
energy cost of certain activities by as much mode after their weightlifting or cardio Human Kinetics:1996; pp 42-90.
as 20-40%.3 Although our team data (cycle) off-court training sessions. 7 Muscles Dynamics Fitness Network.
appears to concur with Bassett’s findings Alternatively, they could have also acci- Caltrac Instruction Manual. Torrance,
wherein the difference between the self- dentally bumped the unit into an alternate CA, 1993.
reported activity versus the Caltrac™ was mode at anytime during the day. Either 8 Poehlman, ET. A review: Exercise and
almost 18%, this corroboration may also situation would have resulted in an overes- its influence on resting energy metabo-
have been influenced by potential user timation of caloric expenditure. ‘ lism in man. Med Sci Sports Exerc
error. The Caltrac™ device has three 1989;21:515-525.
modes of use: ‘regular’, ‘bicycle’, and Conclusions 9 Sallis J. Seven-day physical activity
‘weightlifting’. Regular mode is most often Even though the COSMED® is expensive recall. Med Sci Sports Exerc 2000;
used, however, if one engages in activities and somewhat obtrusive to both peripher- 29:S89-S103.
that require limb movement without total al vision and tennis stroke mechanics, an
MEDICINE & SCIENCE IN TENNIS 9
LE On the Probability of Winning a Tennis Match
FRANC J.G.M. KLAASSEN, PHD1 AND PROF. JAN R. MAGNUS, PHD2
1 Department of Economics, University of Amsterdam, Roetersstraat 11, 1018 WB Amsterdam, The Netherlands.
Tel: +31-20-5254191, Fax: +31-20-5254254. E-mail: email@example.com.
2 CentER for Economic Research, Tilburg University, PO Box 90153, 5000 LE Tilburg, The Netherlands.
Tel: +31-13-4663092, Fax: +31-13-4663066. E-mail: firstname.lastname@example.org.
uring a tennis these respects (which is not surprising,
D match broad-
cast on TV, a num-
because their main objective is to provide
insights into the way players play the
ABOUT THE AUTHORS
Franc Klaassen is Associate Professor of
ber of interesting points). Economics at the University of Amsterdam
statistics are pre- An estimate of the probability that A wins in The Netherlands. He obtained his Ph.D. at
Tilburg University in the Netherlands in
sented to the view- the match, however, provides a direct
2000. His main research interests are empiri-
ers. The most obvi- indication of the likely winner of the cal international economics and finance (for
ous one is the score, match. In addition, the graph of probabili- instance, exchange rates, exports, effects of
but the percentage ties at all points played so far gives an the Euro on trade in the European Union),
of first serves in, the overview of the match development up to econometrics and the statistical analysis of
number of aces, and now; in fact, it makes the information sports, mainly tennis.
Franc Klaassen a few other statistics visible at a glance, so that it may be useful
Jan Magnus is Research Professor of
are also regularly to project the graph on TV and let it sup-
Econometrics at Tilburg University in The
reported on TV. These statistics are then port the commentator in his/her discus- Netherlands. He obtained his Ph.D. at the
discussed by the commentators to provide sion of the match. University of Amsterdam in the Netherlands
a deeper insight into various aspects of the in 1981. His research interests include
match. However, a direct statistic concern- Method econometrics, both methodology and appli-
ing the most important aspect of the To discuss the computation of the proba- cations, matrix calculus, statistics, national
match – namely who will win – is not bilities and thereby the complete graph, accounts estimation and sport statistics, in
shown. In this article we present a method we distinguish between the pre-match
to compute such a statistic: i.e. the proba- probability (the first point of the graph),
bility that a given player will win the and the updated probabilities during the
match. match (rest of the graph). To estimate the probabilities, ‘Tennisprob’ computes the
first probability, we suggest using a trans- probability that A wins the match at the
There are already several methods for cal- formation of the official rankings. This beginning of the point under considera-
culating that probability at the start of the leads to a probability of (e.g.) 80% that tion. This probability is computed exactly
match. One could use the odds from player A will win against B. (not by simulation) and very fast (within a
bookmakers. Alternatively, one could Of course, rankings are just one indicator second). The first input probability is the
employ a statistical model, such as the of the relative strength of the players. If pre-match probability estimated above.
model developed by Clarke and Dyte,1 other information is available, on special The second input consists of the sum of
who use official (ATP and WTA) rating abilities on the court surface and injury two point probabilities: the probability
points to estimate the probability that a problems, for example, then adjustments that A wins a point on serve and the prob-
player will win. In a match between can be made and possibly the ranking- ability that B wins a point on serve. As
players A and B, for instance, this could be based estimate can be improved. before, we have developed a method that
70% for player A. However, as the match Ultimately, there will be one pre-match uses the rankings to estimate this sum.
progresses, new data become available, estimate of e.g. 70%. Klaassen and This leads to e.g. 120%. This estimate
and these can be used to update the pre- Magnus3 show that taking another reason- needs no further adjustment, because the
match probability. For instance, if A has able pre-match estimate shifts the graph probability of interest (that A wins the
lost the first set, then the probability that somewhat, but leaves its form practically match) hardly depends on it. These two
A wins drops: the question is by how unchanged. Hence, the usefulness of the pieces of information are all we need. In
much. This article describes the method of graph in practice does not depend on the particular, we do not need to estimate the
Klaassen and Magnus1 to estimate this exact starting point. two point probabilities - just their sum and
probability. the initial match probability are sufficient.
More specifically, we show how one can To update the estimate as the match pro- This is important, because the latter prob-
compute the probability of A winning, not gresses, we have written a computer pro- abilities are more robust to misspecifica-
only at the start of the match, but also gramme called ‘Tennisprob’. Given the tion. Note also that no information on the
(and in particular) at each point during the rules of the tournament (best-of-three-sets future development of the match is
match. This results in a graph of subse- or best-of-five-sets match, tiebreak in final needed.
quent winning probabilities, which unfolds set or not), the current score, the current
during the match. If the estimate exceeds server, given the statistical assumption that To show how the forecasting procedure
50% for a player, then that player is pre- winning points on serve is an independent works in practice, let us consider the 2003
dicted to win the match. Hence, the graph and identically distributed process (see women’s singles Wimbledon final between
also gives forecasts for the winner of the Klaassen and Magnus2 for a justification of Serena and Venus Williams. Before the
match. this assumption), and given two input match starts, we have to choose the two
input probabilities introduced above. The
The graph and underlying probabilities can first one is the probability that Serena
be informative for TV viewers watching a (player A) wins the match before any
tennis match. After all, the score, point has been played. Because Serena’s
although implying who currently leads the WTA ranking was 1 and Venus’ ranking
match, does not give a perfect indication was 4, we obtain a pre-match estimate of
of the likely winner of the match: a top 81%.
player may still be the favorite after losing However, the knowledge that Venus had
the first set. The score also gives only par- reached the Wimbledon final for the last
tial information on the development of the three years and had won two of them
match: a score of 5-5 can result after 4-4, means that the pure ranking based esti-
but also after 5-0. Summary statistics, such mate was probably too high. On the other
as the percentage first serves in and the hand, Venus was injured. Taking this
number of aces, do not contribute much in information into account, we believed that
MEDICINE & SCIENCE IN TENNIS 10
a reasonable starting probability is 70%. sports science sound
Of course, one may put more weight on
the injury aspect and prefer a higher prob-
ability; in that case the starting point has I’m going to get an I.T.N, My patella tendonitis,
to be adjusted upwards. The second input and win the biggest points. I think is getting well.
probability for ‘Tennisprob’ is the sum of I’ll run all day on hard courts, But with all my Osgood-Schlatters,
both players’ probability of winning a and ignore my aching joints. it’s kind of hard to tell.
point on service. Our ranking-based esti-
mate is 116%, implying an average 58%
probability of winning a point on service. I’ll never lose a match again, Well I thought I was all ready,
This seems reasonable. I’m feeling fairly fit. to play the biggest match,
My strings can stand the tension, But with all this dermatitis
With these two inputs the probability that and I’ve got a flash new kit. perhaps I’d better scratch.
Serena will win the match can be comput-
ed at each point in the match. In fact,
once a point is finished and the new score My approach is scientific, Yeah, perhaps upon reflection,
is known, the updated probability is pre- it’s all sports science sound. I think I’d better rest.
sented within one second. Suppose the And with ground reaction force field shoes, I’ll have another bowl of chips,
second set of the final has just been com- my feet won’t touch the ground. And then I’m off to bed.
pleted (the score from Serena’s point of
view is 4-6/6-4). Then the following graph
can be generated. I’ve got a brand new racket,
it’s simply called ‘THE FORCE’. By Alistair Higham
The graph shows that at the start of the It’s a carbo-techno-jedi bat,
final set (145 points have been played) Dedicated to Dr. Babette Pluim and
of the sci-fi, high-fly sort. Dr. Bruce Elliott
Serena’s probability has shrunk from the
starting point of 70% to about 60%. The
graph also gives a summary of the devel- It’s racket rocket science,
opment of the match so far. Venus’ start with a fuel injected mould.
was overwhelming. Serena came back but It makes Newton’s laws look obsolete,
still lost the first set. The first few games
of the second set were shared, but then
and Astro-physics, old.
Serena took a decisive lead. In the second
part of the second set the graph is quite With strings that move on contact,
stable, indicating that halfway through the to impart the strangest spins.
second set, it was already quite certain The reverse spin, chip-chop sling-shot,
that Serena would win the set. It took
Serena some time before she could end
the second set. During the third set the is one… that doesn’t go in.
graph can be extended.
I’m stuffed full of carbo-hydrate,
Conclusion pancake, pasta, chips and all.
The Serena-Venus match is just one exam-
ple. A graph can be produced for any Hmmm……. I like that carbo-loading,
match for which we have the two pre- it could be my downfall.
match input probabilities and the point-
to-point information as the match unfolds. Yes, I’m ready for the challenge,
Therefore, the approach described above
the battle, the fight, the set.
is a generally applicable forecasting
method. Prepared equipped and ready,
By giving information on the likely winner but I’d better see Babette.
and the past development of the match,
the graph gives extra information besides You see, my forehand is a killer,
the score and the summary statistics that
are commonly presented on TV. It also
but my calf’s a little tight.
makes this information visible at a glance And without my lumbar pillow,
and the graph can be generated instantly. I don’t sleep too well at night.
Hence, it may be interesting to show the
graph on TV at the changes of ends. And with Dr Bruce’s Bio-stuff,
Commentators could then use the graph
to discuss the match, and also to evaluate my serve is very good.
ABOUT THE AUTHOR
the match afterwards. And I would be firing rockets,
Alistair Higham is an L.T.A. Coach Education
if my wrist moved as it should. Tutor, and runs his own business ‘Coaching
References Edge’, working with different sports on the
1 Clarke SR, Dyte D. Using official rating But it feels a little creaky subject of momentum in sport. He was
to simulate major tennis tournaments. Great Britain National Tennis Coach from
Intern Trans Oper Res 2000;7:585- around my ganglion cyst, 1994 to 2001. He is author of two books:
I’ve had tennis leg and elbow, ‘Momentum - The Hidden Force in Tennis’ is
a coaching tool for players and coaches and
2 Klaassen FJGM, JR Magnus. Are points I must have tennis wrist. is used by coaches on the ATP and WTA
in tennis independent and identically world tennis tour. ‘Off the Frame’ is a
distributed? Evidence from a dynamic humorous collection of short stories and
binary panel data model. J Am Stat
And take my topspin backhand,
sketches from Club and County Tennis
Assoc 2001;96: 500-509. the swing path is just fine. based in a fictional Northern County in
3 Klaassen FJGM, JR Magnus. Forecasting But with all my tendonitis, England. For more information, the author
the winner of a tennis match. Eur J can be contacted at
It’s my pain that’s low to high. Coachingedgeuk@aol.com
Oper Res 2003; 148: 257-267.
MEDICINE & SCIENCE IN TENNIS 11
LE Scoring to Remove Long Matches,
Increase Tournament Fairness and Reduce Injuries
GRAHAM POLLARD, PHD AND KEN NOBLE, PHD, 29 BARWON STREET, KALEEN, ACT, AUSTRALIA 2617
E-MAIL GPOLLARD@AUSTARMETRO.COM.AU AND NOBLESOFT@NETSPEED.COM.AU
above, a range of tennis scoring systems is
ABOUT THE AUTHORS
allowable under the rules of tennis. Two
(or more) scoring systems can be com- Emeritus Professor Graham Pollard is a for-
mer professor of applied statistics and pro-
pared for characteristics such as the vice-chancellor of the University of
expected number of points played in a Canberra, Australia. He is a former first
match, the probability each player wins grade tennis player and state squash cham-
the match, and the efficiency of the sys- pion, has a PhD in statistics from the
tem. Given two scoring systems, Scoring Australian National University, and has
System 1 and Scoring System 2, with the international research publications in tennis,
same expected number of points played in squash, theoretical statistics, maths educa-
tion and physics.
Graham Pollard Ken Noble a match, Scoring System 1 is said to be
more efficient (at identifying the better Dr. Ken Noble owns and operates a small
disadvantage or weakness of most ten- player) than Scoring System 2 if Scoring
A nis scoring systems presently in use is
the considerable variation in the duration
System 1 has a higher value for the proba-
bility that the better player wins the
computer software company that markets
specialised energy system modelling soft-
ware. He is a former A-grade tennis and
of matches. Some matches can be reason- match. The efficiencies of scoring systems squash player, and as a leisure time pursuit
ably short whilst others can last a long with differing values for the expected enjoys devising computer programs for
solving puzzles and games.
time. Some other sports (e.g. golf, foot- number of points played can also be evalu-
ball) have a small variation in match dura- ated.1
tion, or even no variation at all. single point under the no-ad rule.
The most commonly used scoring system (Further, it is interesting to note that
Disadvantages in using a scoring system in professional tournaments is the best-of- under the no-ad rule, there can be a total
with considerable variation in match dura- three tiebreak sets system. In this paper of four points to one service court and
tion include: we use several constructs to identify an only three to the other, involving a clear
• The winner of a long match or sequence alternative scoring system with a substan- lack of symmetry. With a draw at deuce
of long matches can be relatively tired, tially reduced variation of duration (num- this lack of symmetry is removed. It can
and so can be disadvantaged when play- ber of points played). Other characteristics also be seen that, under the draw at deuce
ing a fresher opponent in the next of this alternative scoring system such as construct, a point such as 40-30 becomes
round. Thus, scoring systems with a big the expected number of points played, and considerably more important and exciting
variation in match duration can be unfair the probability each player wins are shown than under the present game-finishing
in the tournament setting. to have acceptable values. structures.)
• A long match or sequence of long The alternative scoring system analysed in
matches for a player can lead to injuries this paper makes use of the deciding In this paper we show that a key to achiev-
for that player. Indeed, the very need to match tiebreak game concept in order to ing a substantial reduction in the variation
train for the reasonable likelihood of reduce the variation in match duration. of the duration of a match, is to make use
long matches can lead to additional and This variation is further reduced by using of a deciding match tiebreak game, and to
arguably unnecessary strain on players, two new constructs. allow a win/draw/loss option at the set and
and injuries. The first new construct involves not play- at the game level.
• Long matches can lead to considerable ing a tiebreak game if the game score Under the present rules a set of tennis is
delay in the starting time of matches reaches 6-6 in a set, but simply declaring won 6-0, 6-1, 6-2, 6-3, 6-4, 7-5 or 7-6.
scheduled to follow. An enhanced relia- the set a draw, with the match being won Thus, unless a tiebreak game is required, a
bility of the scheduled starting time for by a set score of 11/2-0 or 11/2-1/2, unless set of tennis is a hybrid of the best-of-ten
matches would be attractive to players, one set all is reached in which case a games system and the best-of-12 games
spectators and officials. deciding match tiebreak game is played. system. It can be shown that, in some dou-
• Television broadcasters would see an Since a match can be won by a set score of bles contexts and in singles with an ‘end
advantage in reducing the likelihood of 11/2-0 or 11/2-1/2, we prefer to describe this effect’ (e.g. wind effect or sun effect), the
very long matches, and knowing that a as a best-of-two sets match. best-of-ten games (and hence a set of ten-
match is almost certain to last less than a The drawn set construct clearly reduces nis under the present rules) is unfair.2 By
given duration. the variation of the match duration. We contrast, in these doubles and singles with
have also shown that when playing no-ad an end effect, best-of-four games, best-of-
There are several approved scoring system games and a best-of-two sets match with a eight games, best-of-12 games, can be
options within the present rules of tennis TB (7,2) deciding match tiebreak game, it shown to be fair. In order to achieve fair-
(see the ITF publication, Rules of Tennis is (perhaps surprisingly) more efficient not ness in these broader contexts, we have
2003). For example, we have the best-of- to play the tiebreak game at 6-6 in the first taken a set of tennis in our alternative sys-
three and best-of-five sets systems, we two sets than it is to play it. tem to be the best of 12 games. Thus,
have no-ad games in which only one point given games can be drawn, a player can
is played if deuce is reached, and we have The second new construct for reducing win a set 61/2-0, 61/2-1/2, 61/2-1, …,
‘short’ sets that have completed game variation is an analogous one within the 61/2-51/2, or the set is drawn at 6-6.
scores of 4-0, 4-1, 4-2, 5-3 or 5-4 follow- game structure. It involves declaring a The alternative scoring system considered
ing a tiebreak game at 4-4. We also have game a draw if deuce is reached. Thus, if in this paper has one further refinement.
the first to seven (or first to ten) lead by at deuce is reached each player is awarded Since games are shorter under the
least two points deciding match tiebreak half a game. The variation of match dura- win/draw/loss game modification, and as
game (denoted here by TB (7,2) or TB tion is reduced using this construct. We no tiebreak games are played in the first
(10,2)) that can be played instead of the have also shown that when playing the two sets, a longer deciding match tiebreak
third or fifth set in a best-of-three or best- best of two (win/draw/loss) sets with a TB game can be justified as a third set. As TB
of-five sets match. (7,2) deciding match tiebreak game, it is (7,2) and TB (10,2) are both unfair in the
By using different combinations of the var- more efficient to declare a service game a contexts mentioned above, we modelled
ious scoring system options mentioned draw if deuce is reached than it is to play a the first to at least nine points lead by at
MEDICINE & SCIENCE IN TENNIS 12
least two points tiebreak game, TB (9,2), The following observations can be made from means ranging from 137.0 to 146.3). It
which has been shown to be fair in the the tables: can be seen that p(A wins) can be
above-mentioned contexts.3 • The variation in match duration is sub- increased at the expense of increasing
Thus, the alternative scoring system con- stantially smaller for the alternative scor- the standard deviation.
sidered in this paper can be described as a ing system. For example, the standard
best-of-two sets system that can be won by deviation of the duration of a match In conclusion we note that the best-of-
a set score of 11/2-0 or 11/2-1/2, unless one ranges from 40.0 points to 42.2 points in three tiebreak sets scoring system has the
set all is reached in which case a TB (9,2) Table 1, whereas it ranges from only disadvantage that some matches last a long
deciding match tiebreak game is played. 10.3 to 14.9 in Table 2. time. For example, one match in fifty lasts
In our modelling we have made the stan- • The value of the difference between the more than about 240 points.
dard assumptions that Player A has a con- 98% point and the mean ranges from 74 Combining several constructs including
stant probability pa of winning a point on points to 91 points in Table 1 whereas it drawn games and drawn sets, an alterna-
his/her service, whilst Player B has a con- ranges from only 22 to 30 points in tive best-of-two sets system has been
stant probability pb of winning a point on Table 2, highlighting the substantial shown to have the attractive characteristic
his/her service, and the points are inde- reduction in variability for the alterna- of a much smaller variation of match dura-
pendent. The tabled results for each tive system. It is noted however that the tion. Indeed, forty-nine matches in every
parameter set are those of 1,000,000 sim- 2% points for the two systems are virtu- fifty have been shown to last less than 150
ulated matches as this is a sufficient num- ally identical. points.
ber for appropriate accuracy.4 • The mean duration varies from 148.8
points to 168.9 points or by about 20 Other statistical measures of the alterna-
Table 1 gives results for the present best- points in Table 1, whereas it varies by tive scoring system have been shown to be
of-three tiebreak sets scoring system. For only about 7 points in Table 2. Thus, the acceptable. Thus, it has been demonstrat-
men’s singles, the probability a player wins present best-of-three tiebreak sets sys- ed that it is possible to remove the occur-
a point on service averages, over a range of tem not only has substantially greater rence of long matches from tournament
surfaces, about 0.61. For women’s singles variation in duration for any particular play.
the average is closer to 0.55 and for men’s type of match (or any particular pair of
doubles it is closer to 0.7 and even higher parameters (pa, pb)), but it also has References
for players with very strong serves. In the greater variation across the various types 1 Miles RE. Symmetric sequential analy-
table we have given results for parameters of matches (men’s, women’s, doubles), sis: the efficiencies of sports scoring
averaging 0.5, 0.6, 0.7 and 0.75. Thus, the adding further to the unpredictability of systems (with particular reference to
table gives results for a large range of sin- the length of matches. those of tennis). J Royal Stat Soc B
gles and doubles matches. It can be seen • When pa is not equal to pb, the probabili- 1984;46(1):93-108.
from Table 1 that when pa = 0.62 and pb = ty player A wins the match is somewhat 2 Pollard G and Noble K. A solution to
0.58, the probability Player A wins the smaller for Table 2 than for Table 1 the unfairness of tiebreak tennis dou-
match is 0.697, and the mean and stan- (although there is very little difference in bles. In: Miller S (ed.). Tennis Science
dard deviation of the number of points columns 11 and 12). This is not particu- and Technology 2. London: Interna-
played is 160.0 and 41.5. Two per cent of larly surprising as matches are shorter in tional Tennis Federation 2003: 325-332.
matches have a duration of less than or Table 2. The values for the probability 3 Pollard G and Noble K. A solution to
equal to 93 points, and 2% of matches that A wins in Table 2 can be increased the unfairness of the tiebreak game
have a duration of greater than or equal to by modifying the alternative system and when used in tennis doubles. In: Cohen
246 points. using a longer third set or deciding G and Langtry T (eds). Proceedings of
match tiebreak game. Alternatively this the 6th Australian conference on
Table 2 gives the corresponding results for probability in Table 2 can be substantial- Mathematics and Computers in Sport.
the alternative best-of-two sets scoring sys- ly increased by modifying the alternative Sydney: University of Technology
tem we have described (each set is the system to a best-of-four sets in which Sydney Printing Services 2002: 231-235.
best-of-12 games with a drawn set if the each set is a best-of-eight games whilst 4 Pollard G and Noble K. A new tiebreak
game score reaches 6-6; games are drawn the rest of the system remains game with four proposed applications.
if deuce is reached; if a deciding match unchanged. This best-of-four sets alter- In: Miller S (ed.) Tennis Science and
tiebreak is needed as a third set it is a TB native system has standard deviations Technology 2. London: International
(9,2) tiebreak game). ranging from about 21.6 to 26.4 (and Tennis Federation 2003:317-324.
Table 1 Best of Three Tiebreak Sets
1 2 3 4 5 6 7 8 9 10 11 12
pa 0.5 0.52 0.54 0.6 0.62 0.64 0.7 0.72 0.74 0.75 0.77 0.79
pb 0.5 0.48 0.46 0.6 0.58 0.56 0.7 0.68 0.66 0.75 0.73 0.71
p (A wins match) 0.500 0.704 0.858 0.500 0.697 0.849 0.500 0.680 0.824 0.499 0.669 0.809
mean 164.6 160.2 148.8 164.0 160.0 149.6 165.6 162.4 154.0 168.9 166.2 158.8
sd 42.0 42.2 41.4 41.2 41.5 40.7 40.4 40.6 40.4 40.0 40.3 40.4
2% point 94 91 85 95 93 87 98 96 92 100 98 95
98% point 251 248 240 248 246 239 245 244 239 243 242 239
98% point - mean 86 88 91 84 86 89 79 82 85 74 76 80
Table 2 The Alternative Scoring System
1 2 3 4 5 6 7 8 9 10 11 12
pa 0.5 0.52 0.54 0.6 0.62 0.64 0.7 0.72 0.74 0.75 0.77 0.79
pb 0.5 0.48 0.46 0.6 0.58 0.56 0.7 0.68 0.66 0.75 0.73 0.71
p (A wins match) 0.500 0.665 0.801 0.500 0.666 0.802 0.500 0.666 0.804 0.499 0.668 0.806
mean 122.3 121.0 117.4 121.9 120.7 117.4 120.5 119.4 116.6 119.1 118.2 115.8
sd 13.6 14.0 14.9 12.9 13.3 14.1 11.2 11.5 12.1 10.3 10.5 10.9
2% point 93 91 86 94 92 88 97 95 91 98 97 93
98% point 149 148 147 147 147 146 144 143 142 141 141 139
98% point - mean 27 27 30 25 26 29 24 24 25 22 23 23
MEDICINE & SCIENCE IN TENNIS 13
Letter to the Editor
I read the article ‘Comparison of Abdominal Muscle Patterning in the Tennis Serve using Different Footwork Techniques’ in Medicine
and Science in Tennis with great interest. I regard the question of foot-up or foot-back as a fascinating issue, especially in the women’s
game. Both techniques have advantages and disadvantages, depending on the type, size and style of game which the player adopts.
To imply that, because a player changed from foot-back to foot-up, they have achieved their true potential is a little speculative, as
many variables would contribute to the development of a players success (Medicine and Science in Tennis 2003;8(1):11).
Not only could this assumption be invalid, but coaches may well accept this information on face value and start changing their players’
serving style on the basis of this premise.
Reply to Letter to the Editor
HRVOJE ZMAJIC, ITF/TENNIS EUROPE DEVELOPMENT OFFICER, ZAGREB, CROATIA
irstly, I would like to thank you for ed to publish the results for another player while using the foot-back technique. Very
F your interest in my article. In the mid-
dle paragraph on page 11, I wrote: ‘The
that we examined at the same time. Both
players had an excellent serve (in the
tall players like Krajicek, Ivanisevic,
Philipoussis or Rusedski all use the foot-up
results of the given EMG signal analysis, as coaches’ opinion). The 16-year-old player technique. A possible explanation is a
well as the facts given in the bibliography (A) was right-handed and 207 cm tall. The longer moment of inertia of the back foot,
(Nos. 2 and 4), indicate that if he applied other player (B) was aged 32 at the time, which is further away of the centre of
the Foot Up footwork technique while left-handed and 167 cm tall. rotation and causes less acceleration of the
serving, he would better realise his true dominant side of the body with the foot-
potential. Now, six years later, he uses the Similarities can be seen in the signals of back technique. A possible solution for tall
Foot Up technique and has reached ATP the left and right rectus abdominis in both players who use the foot-back technique is
ranking 170.’ players. In both, the majority of the mus- to land on the back foot, as Boris Becker
cle activity is produced with the foot-up did.
This means that the player would be able technique. Different activity of the right
to better realise his true potential in serv- (player A) and left (player B) obliquus
ing. To avoid any misunderstanding or externus is recorded. A greater amount of
incorrect interpretation, the next sentence muscle activity is produced by player B
should be: ‘After the discussion with the with both footwork techniques. The dif-
coach, the player adopted the Foot-up ferences can be explained by the following
serving technique. We are convinced that hypothesis.
this decision has contributed to the fact
that, six years later, he has reached ATP Comparing the constitutional characteris-
ranking 170.’ tics of top players, we see that players of
As an additional argument that supports average height, such as Agassi, Sampras
the results described in this article, I decid- and Ferreira, are very successful in serving
Right obliquues externus Right rectus abdominis
We can assume that taller players have
greater relative explosive leg power and
strength in the lower trunk muscles. The
signals recorded in our experiment support
the idea that such players can use the
lower trunk muscles almost simultaneous-
ly, in order to achieve optimal acceleration
of the dominant side of the body. The
smaller number of movements and the
Left obliquues externus Left rectus abdominis
wider base of support (balance) can also
positively influence the precision and
accuracy of the serve while using foot-back
This hypothesis certainly needs to be test-
ed on a larger number of players. I would
also like to stress that neither technique is
better by definition, but coaches should
take constitutional characteristics and
serve effectiveness into account when
deciding which foot-work technique is
Figure 1 Maximum peak signals of player B best for an individual player.
MEDICINE & SCIENCE IN TENNIS 14
Development of the Kinaesthetic Channel
in Tennis Training
FERNANDO SEGAL, AV. PUEYRREDON 1376 1 PISO, BUENOS AIRES, ARGENTINA
tennis player’s fying the sensitive-sensorial afferences.
A degree of devel-
opment is shown by
Anochin1, when formulating his neuro-
motor model, underlines the importance
ABOUT THE AUTHOR
Fernando Segal was in charge of the
his ability to estab- of the data in the efferent synthesis (the National Development Programme of
lish patterns (tacti- information we have about the move- Argentine Tennis Federation. This pro-
gramme brings a new generation of
cal, technical, physi- ment), and in the returning afferences (as
Argentinean players to the international ten-
cal, biomechanical a way to point out the mistakes in the nis circuit, such as: Guillermo Coria, David
and mental) that movement perfomed). Bernsteijn1 empha- Nalbandian, Clarisa Fernandez, José
can resolve as many sises in a more particular way that we are Acasuso, Maria Salerni and others.
variables of plays always conscious of the sensorial signal in He has written 8 books about several
and throws as possi- the highest level, ‘which is determined by themes of development players, organisa-
Fernando Segal ble in his or her per- a certain intention in singular conditions, tions and projects. Many of them are used
for various clubs and organisations of
formance, effective- defined as the intention and / or motor
ly and efficiency. The player inputs the task that turns out to be the starting point
information through three channels: the for each construction (stroke)’. At the
visual channel (generally the most fre- same time, this implies that various factors
quently-used channel from the start, in lead up to the impact, including the con- Conclusions
both instruction and training), the auditive servation and transmission of force, the Any variation in the recognition, interpre-
channel (hearing the acoustic rhythm gen- precision of the movement and correct co- tation and execution of a movement needs
erated by the stroke and the bouncing of ordination of motor parts. a programming component, that gives
the ball) and the kinaesthetic channel value to the execution (tactical aspect), an
(through the sensitivity of touch in the Once the stroke has been executed, the execution component, that makes what
corporal aspect, in the transmission of the first and essential condition is the kinaes- has been programmed with a sequence
stroke through the hand, and in the posi- thetic afferent way. This is referred to a integrated by parts of the movement
tion of the body, with sense stimuli trans- pool of impulses that go from the active (technical aspect), and a component that
mitted by the body and the support of the part of the body to the brain, carrying delves deeper into the kinesthetic channel,
feet). information about the special position of by means of some practical exercises that,
the body, the muscular intensity and tone, when applied, allow us to improve the
The concept of working on kinaesthetic the movement and the quality of the exe- sensations of the relationship between the
sensitivity is heavily underrated in compar- cution.4 Without recognising these afferent hand, the racket and the stroke: to hit, to
ison with other aspects3. Nevertheless, the data, the movement would lose its efferent reduce, to accelerate, to accompany and to
process of mental decisions on the stroke basis and its quality of development block,5 with the subsequent development
(both strategic and tactical), its tactical would be minimised. Finally, Luria2 states of a technical and tactical amplitude of
and biomechanical execution and its phys- that ‘the construction of a voluntary resources.
ical preparation are reflected in an impact, movement includes a whole system of
in which information about the quality efferent and afferent rings which are References
and the result of the executed stroke is placed in different sections and at different 1 Anochin PK, Bernsteijn NA, and
collected and carried to the brain. levels of the central nerve system. Each Sokolov EN. Neuro-physiology and
one of the rings belonging to this system cybernetics. Rome: Ubaldini, 1973.
Results and discussion has a specific function, securing the motor 2 Luria AR. How the brain works.
The most perceptive cells are in the hand formation, the spatial and kinaesthetic Bologna: Mulino, 1977.
and feet. Consequently, every voluntary schema of the movement, the tone and 3 McArdle WD, Katch FI, and Katch VL.
human action with an objective is always the co-ordination of the muscular groups.’ Exercise physiology. Baltimore:
subject to a dominant motive (tactical This system feeds back information and Williams & Wilkins,1996.
objective). It requires a programme that integrates a series of afferences that, once 4 Raimundi P. Kinesiology and psycho-
elaborate the perceptive stimulus – in this they are recognised, allow a bigger and motricity. Sperling & Kupfer, 1998.
case, the kinaesthetic ones – and an internal more permanent organisation of perform- 5 Segal F. SAF. Sistema Analítico
dialogue that determine the action, decodi- ance, with improved quality. Formativo,1997.
Internal Impingement in the Etiology of Rotator Cuff Tendinosis Revisited
BUDOFF JE, NIRSCHL RP, ILAHI OA, RODIN DM
he theory of internal impingement holds being treated for partial-thickness undersur- thickness rotator cuff tears also had superi-
T that, in overhead athletes, repeated con-
tact between the undersurface of the rotator
face rotator cuff tears.
The study was a retrospective case series.
or labral lesions. A statistically significant
increased prevalence of superior labral
cuff and the posterosuperior glenoid rim We retrospectively reviewed the records of lesions in the dominant shoulder was seen
leads to articular-sided partial-thickness 75 shoulders arthroscopically treated for (P =.03). In addition, our patients who
rotator cuff tears and superior labral lesions. partial-thickness articular-sided rotator engaged in overhand throwing had signifi-
However, we have noted this same constel- cuff tears. With the exception of one pro- cantly fewer superior labral lesions in the
lation of lesions in our general patient popu- fessional tennis player, no patients were dominant shoulders than did nonthrowers
lation. These recreational athletic patients playing sports at a professional or major (P =.017). Conclusions: The ‘kissing
do not routinely assume the position of college level. No professional or collegiate lesions’ of undersurface rotator cuff tears
extreme abduction and external rotation, throwing athletes were included. The and posterosuperior labral damage may be
and thus are unlikely to experience signifi- prevalence of these lesions and their asso- explained by mechanisms other than
cant internal impingement forces. The goal ciation with recreational athletics was ‘internal impingement’.
of this study was to document the preva- noted. We found that 55 of 75 (73.3%) Published in:
lence of superior labral lesions in patients shoulders with articular-sided partial- ARTHROSCOPY 2003;19(8):810-814.
MEDICINE & SCIENCE IN TENNIS 15
International Comparison of Tennis Success
VEERLE DE BOSSCHER1, PAUL DE KNOP1, IVO VAN AKEN2 AND BRUNO HEYNDELS1
1 Free University of Brussels, Fac. LK, BSVB, Pleinlaan 2, 1050 Brussels, Belgium
2 Flemish Tennis Federation (VTV), Edegemse Steenweg 100, 2610 Wilrijk, Belgium
olitics and a lack players. By calculating the rankings of
P of effective
sports policies are
players in the ATP and WTA top 100, a
total score can be given for each country.
ABOUT THE AUTHORS
Veerle de Bosscher is an assistant at the
faculty of Physical Education of the Free
often blamed for The sum of ATP and WTA singles ranking University of Brussels (VUB), Belgium. She
inferior achieve- was calculated. Doubles where not includ- graduated in Physical Education and earned
ments in sport. Still, ed, as there is a high correlation with the both a master’s degree in sports manage-
the nature of effi- singles result.4 There is also a close correla- ment and in training/coaching.
cient sports policies tion with the top 200 and 500 players, and
is not completely even with the number of players. The Paul De Knop has a PhD in Physical
clear.2 In fact, it is same method was applied for the top Education at the Faculty of Physical
Education of the Free University of Brussels
not even clear how 1,000 players. The top 100 and top 1,000
(VUB), Belgium, graduated in leisure studies
Veerle De Bosscher to distinguish suc- may give different interpretation of ‘suc- at the same university and earned a Master
cessful from unsuc- cess’. Degree in Sports Sociology and Sports
cessful countries in a given discipline, or in The literature suggests that international Management from the University of
sports in general. A primary aim of this success depends heavily on socio-economic Leicester (UK). He is a full time professor at
paper is to do precisely that. Using tennis factors.1,5,6,7 The main factors mentioned the VUB and is the head of the Youth
as a case, we demonstrate how different are population, wealth, area, urbanisation, Advisory Centre for Sport, an interdiscipli-
nary research and advisory center.
parameters can be developed for a coun- religion and the political system.2 The
try’s success. starting point for our empirical work is a Bruno Heyndels, PhD, is senior lecturer at
Typically, success is expressed in absolute simple ordinary least square estimation the Free University of Brussels (Vrije
terms. Nevertheless, such comparisons are (regression analysis) of a reduced form Universiteit Brussel). His research interests
obviously biased by structural differences model that captures the main macro- are in the field of public choice, economics
in national socio-economic situation, such determinants of absolute success. This esti- of sports, cultural economics and economic
as gross domestic product, population, mation gives information on the extent to psychology.
area, etc. As such, indicators of absolute which absolute success is explained by
Ivo Van Aken is the performance director of
success carry little information on how macro-(economic) determinants. This is the Flemish League of the Belgian Tennis
successful or efficient countries ‘really’ are the definition of relative success. association. He is Fed Cup Captain and was
in allocating their (scarce) resources. Such Olympic Coach in Barcelona, Atlanta and
information can only be given by indica- The basic estimation equation for tennis Sydney. He is a member of the department
tors of relative success. We offer a method success is: of Top Sport of the Belgian Olympic
to measure relative success through an AS-Olympic Games = 0 + 1 POP + 2 Committee.
abstraction of the macro-economic deter- GDP + 3 AREA + 4 URB + 5 RELI +
minants. Countries are then placed in 6 GOV + URB = urbanisation
comparable positions with regard to top- RELI = religion
level performance in sports. Where: GOV = type of government
AS = absolute success
Method POP = population Results and discussion
International rankings (ATP and WTA) GDP = gross domestic product Table 2 shows that 46 % of the variation
are based on the success of individual AREA = the size of the country in tennis success can be attributed to dif-
Table 1 Ordinary least square estimates: explaining variance for international tennis success
Dependent variable Independent variables t-value Level of significance Adjusted R square Standard error
of the estimate
Population 3,057 0,003
Tennis success top 100 GDP/cap 3,428 0,001
(WTA+ATP) Area 2,448 0,17 0,46 4157
Protestant countries 2,304 0,24
Table 2 Relative success: residuals from AS-1000 and AS-100 regressions (Residual R)
Country Predicted AS-100 R Players Country Predicted AS-1000 R Players
1. Spain 3611 22208 18597 23 1. Spain 5504 29016 23512 128
2. USA 21286 37463 16177 26 2. USA 29203 47157 17954 184
3. Belgium 3780 15112 11332 6 3. France 8425 22305 13880 127
4. France 5685 14992 9307 19 4. Argentina 5463 16862 11399 77
5. Slovakia 459 4686 4227 6 5. Belgium 5927 16486 10559 23
6. Croatia -496 3349 3845 6 6. Czech 2200 11665 9465 85
7. Czech 1217 4867 3650 6 7. Slovakia 1123 7150 6027 39
8. Russia 14721 18014 3293 16 8. Croatia -259 5614 5873 37
9. Argentina 3734 6967 3233 8 9. Italy 7459 12167 4708 108
10. Switzerland 4367 6962 2595 5 10. Germany 9127 12779 3652 120
11. Yugoslavia -970 1187 2157 1 11. Russia 19488 22585 3097 93
12. Armenia -1133 798 1931 1 12. Yugoslavia -979 1910 2889 16
13. Chilli 1202 2932 1730 3 13. Bulgaria 66 2333 2267 17
14. Slovenia 691 2376 1685 3 14. Switzerland 6791 8886 2095 24
15. Morocco 206 1851 1645 2 15. Armenia -1176 798 1974 1
MEDICINE & SCIENCE IN TENNIS 16
ferences in population, wealth, area and wealth and large population, it still has a References
religion. Population alone explains 23%. very high residual. Belgium, the Czech 1 Colwell J. Socio-cultural determinants
Republic and Croatia, with six players in of Olympic success. In: J. Segrave and
A regression analysis serves two purposes. the top 100, are more successful than e.g. D. D. (Eds.). The Olympic Games in
Firstly, it identifies the determinants for Russia. Besides the differences between transition. Champaign: Human Kinetics
international success at the macro-level. absolute and relative success, we also find Publishers, 1981.
Secondly, the analysis of the residuals differences between the top 100 and top 2 De Bosscher V, De Knop P. The influ-
allows us to compare countries on a ceteris 1,000 players. While the top 1,000 can ence of sports policies on international
paribus basis, so that we can define their serve as an indicator of the available success: An international comparative
relative success. A case-by-case analysis of resources for tennis in any one country, study. In: Proceedings of the 9th World
each country gives an objective answer to the top 100 may be a better parameter of Sport for All Congress. ‘Sport for all
the question: ‘what do successful countries how these resources are invested. In some and elite sport: rivals or partners?
control in terms of socio-economic cir- countries, such as Argentina, Italy, (pp.31). Arnhem: IOC, 2002.
cumstances?’. The residuals – the unex- Bulgaria, and the UK, success diminishes 3 De Bosscher V, De Knop P, Heyndels
plained variation – are taken as an indica- when the top 100 players are used for a B. The influence of sports policies on
tor of this relative success, and as such, are definition of absolute success. international success of countries: equal
considered a more efficient measure of opportunities or not? 11th congress of
sporting success. Conclusion the European association for sport man-
A country above the regression line (repre- By monitoring exogenous influences on agement. Stockholm, 4-7 September
sented by the residual) performs better success, the methodology allows successful 2003.
than would be expected on the basis of the countries and effective sports policies to 4 De Bosscher V, De Knop P, Van Aken
socio-economic situation. The reason for be identified. While our focus is on tennis, I, Heyndels B. Comparing tennis success
this might lie in the efficiency of sports the method proposed has a much wider among countries. Presented at the ITF
policies. Table 2 shows the differences application. Tennis was taken as a case world-wide coaches workshop.
between absolute and relative success for study in order to further determine the Villamoura, 20-26 October 2003.
the 15 best performing countries, using importance of an efficient and effective 5 Den Butter F AG, Van der Tak CM.
the top 100 and top 1,000 players, given sports policy for international success. To Olympic medals as an indicator of social
the residual: R(esidual) = A(bsolute)- examine the effect of sports policies on welfare. Soc Indic Res 1995;35:27-37.
P(redicted). national sporting success, external factors 6 Van Bottenburg M. Het topsportkli-
should be eliminated as far as possible. maat in Nederland. ’s-Hertogenbosch:
The table shows that monitoring of socio- The higher efficiency results from the fact Diopter-Janssens en van Bottenburg bv,
economic determinants presents a differ- that the method boils down to monitoring 2000.
ent image of tennis success. A clear – the systematic influences on macro-deter- 7 Stamm H, Lamprecht M. Sydney 2000
though not unexpected – result of this minants. – The best games ever? World sport and
analysis is that the U.S. is no longer the The model for explaining international relationships of structural dependency.
most successful nation in tennis. Regard- success could be further refined. A major Summary of a paper presented at the
less of whether we use information on the route for further research involves taking 1st World Congress of the Sociology of
top 1,000 players or only the top 100, cultural effects more closely into consider- Sport. Seoul, Korea, 2001. Webpage
Spain is the most successful country. ation. Sports and its organisation remain www.lssfb.ch/download/ISSA_Seoul.pdf
It should nevertheless be noted that the specific to culture, which is revealed in
U.S. remains successful. ‘Despite’ its different ways.
E Science and the Major Racket Sports: a Review
ADRIAN LEES, RESEARCH INSTITUTE FOR SPORT AND EXERCISE SCIENCES, LIVERPOOL JOHN MOORES UNIVERSITY,
HENRY COTTON CAMPUS, 15-21 WEBSTER STREET, LIVERPOOL L3 2ET, UK
he major racket sports include bad- ing programmes to improve players’ fit- mechanisms of both performance and
T minton, squash, table tennis and ten-
nis. The growth of sports science and the
ness; guide players in nutritional and psy-
chological preparation for play; inform
injury. They have provided a unique chal-
lenge to sports engineers in relation to
commercialisation of racket sports in players of the strategy and tactics used by equipment performance and interaction
recent years have focused attention on themselves and their opponents; provide with the player. Racket sports have
improved performance and this has led to insight into the technical performance of encouraged developments in notational
a more detailed study and understanding skills; understand the effect of equipment analysis both in terms of analytical proce-
of all aspects of racket sports. The aim on play; and accelerate the recovery from dures and the conceptualisation of strategy
here, therefore, is to review recent devel- racket-arm injuries. Racket sports have and tactics. Racket sports have provided a
opments of the application of science to also posed a unique challenge to scientists vehicle for investigating fast interceptive
racket sports. The scientific disciplines of and have provided vehicles for developing actions, hand-eye co-ordination and per-
sports physiology and nutrition, notational scientific methodology. Racket sports pro- ception-action coupling in the field of
analysis, sports biomechanics, sports medi- vide a good model for investigating the motor control. In conclusion, science has
cine, sports engineering, sports psychology interplay between aerobic and anaerobic contributed considerably to our knowledge
and motor skills are briefly considered in metabolism and the effect of nutrition, and understanding of racket sports, and
turn. It is evident from these reviews that heat and fatigue on performance. They racket sports have contributed to science
a great deal of scientific endeavour has have driven the development of mathe- by providing unique challenges to
been applied to racket sports, but this is matical solutions for multi-segment inter- researchers.
variable across both the racket sports and actions within the racket arm during the
the scientific disciplines. A scientific performance of shots, which have con- Published in:
approach has helped to: implement train- tributed to our understanding of the J SPORTS SCI 2003;21(9):707-732.
MEDICINE & SCIENCE IN TENNIS 17
The 13th ITF Worldwide Coaches Workshop
he 13th ITF Worldwide Coaches
T Workshop - the showpiece of the ITF’s
coaches’ education programme - was held
in Vilamoura, Portugal from October 20
to October 26. The biennial event was
organised by the ITF and the Portuguese
Tennis Federation (FPT) and attracted
more than 300 coaches from 100 countries
worldwide. It was the first time for ten
years that this event had been held in
Europe. The workshop theme was
‘Applied Sport Science for High
Performance Tennis’ and it provided an
ideal setting for coaches and other profes-
sionals involved in tennis to learn and
interact. Speakers included some of the Speakers of the workshop
tennis world’s most highly respected scien-
tists, coaches and coach educators and we
would like to take this opportunity to for tennis. Dr. Babette Pluim and Frank many coaches have taken the opportunity
thank them for their efforts in making the van Fraaijenhoven, both from the Dutch to join us in Vilamoura.”
Workshop such a success. Tennis Federation, illustrated how doctors
and coaches can improve their communi- FPT President and co-host Manuel Valle-
Among the coaches presenting at this cation and interaction by given a joint Domingues also confirmed Portugal’s
year’s Workshop were Bob Brett, former presentation on this topic. commitment to coaches education by sign-
coach to Boris Becker; Niki Pilic, ex-top ing an agreement with the ITF to use the
ten player and former doubles world No. Also, for the first time at a worldwide ITF’s material in Portugal’s coaches educa-
1; Emilio Sánchez Vicario, director of a coaches workshop, there was an opportu- tion programme. More than 80 countries
High Performance Centre in Barcelona, nity for young investigators and coaches to worldwide are currently using the ITF
ex-top ten player and former doubles present their work and ideas during the coaching syllabi in their coaching pro-
world No.1; and Javier Duarte, Spain’s ‘free communication’ sessions. grammes.
former Davis Cup captain and ex-coach of
Alex Corretja and Alberto Berasategui. “It’s been a fantastic week,” said Richard
Gonzales, School Tennis Initiative Co-
Several scientists and medics had been ordinator of Uruguay. “The quality of the CONFERENCE CALENDAR
invited to present. Prof. Karl Weber from presentations both on and off court by 10-13 D ECEMBER 2003
2nd Symposium for Tennis and Ski
the Sports University in Cologne tackled experts in all aspects of high performance Medicine, St. Anton am Arlberg, Austria
the issue of high speed training on the ten- tennis has been first class. Plus the chance Information: Dr. Rudi Schabus, Sport &
nis court in a very elegant, albeit compli- to mix with coaches from all over the Trauma e.v., Liechtenstraße 53, A-1090
cated, presentation with many interesting world, makes this event very special.” Vienna, Austria.
Fax + 43 1 40180 780,
videos. Dr. Joachim Mester from the same E-mail R.Schabus@sport-trauma.at
University took us into the future with his Speaking at the closing dinner, ITF Website www.sport-trauma.at
elaborate presentation on e-learning. President Francesco Ricci Bitti said: “The
Catherina Ortega (WTA) discussed the ITF regards its relationship with the coach- Conferences in 2004
15-18 J ANUARY , 2004
issue of core stability. Vitor Cabral, coach ing community as one of the most effec- 9th Australian Tennis Conference,
and scientist, talked about the physical tive ways of growing the sport of tennis Melbourne, Australia – leading into The
preparation for tennis (strength training), throughout the world.. Coaches play a Australian Open
Information: Sarah Foott: Tennis Coaches
whereas Dr. Ann Quinn showed how vital role in the development of players at Australia, Private Bag 6060, Richmond Sth,
players can mentally prepare themselves every level and I am gratified to see that so Vic, 3121 Australia
Tel + 61-418-995-843 Fax +61-3-9824-8050
19-20 J UNE 2004
STMS 6th International Conference on
Medicine and Science in Tennis- The LTA
Sports Science and Sports Medicine
Conference, London, UK. Held in conjunc-
tion with the Wimbledon Championships.
Information: Dr. Michael Turner, LTA,
The Queens Club, London W14 9EG,
Tel + 44 207 381 7071 Fax + 44 207 381 3001
13-16 S EPTEMBER 2004
5th International Conference on the
Engineering of Sport, University of
California, Davis, USA
Information: Mont Hubbard, Conference
Organizer, Department of Mechanical and
Aeronautical Engineering, University of
California, Davis, California 95616, USA.
Tel +530-752-6450 Fax +1-530-752-4158
Participants of the workshop
MEDICINE & SCIENCE IN TENNIS 18
Special Offer for STMS Members
Journal Science and Medicine in Sport (Tennis Edition) and
Sports Medicine Australia 2003 Conference, Book of Tennis
Tennis Australia and Sports Medicine Australia (SMA) are offering STMS members a package deal of
the Journal of Science and Medicine in Sport (Tennis edition) plus a book of Tennis Abstracts from the
2003 Australian Conference of Science and Medicine in Sport.
The Tennis edition of the JSMS features multi-disciplinary research in tennis from physiology,
biomechanics, physiotherapy, medicine and technology. Sports scientists involved in this issue include
Dr Babette Pluim (Dutch Tennis Federation), Prof. Bruce Elliott (University of Western Australia),
Dr Miguel Crespo and Machar Reid (ITF), and Prof. Howard Brody (University of Pennsylvania).
The Book of Abstracts is not available anywhere else, and with the Conference recently held in October,
it is your opportunity to receive the latest tennis research.
For further information or to purchase your copy of the JSMS (Tennis Edition) and Book of Tennis
Abstracts please contact Dr Alan Pearce at Tennis Australia on email@example.com or
phone +61 3 9286 1177.
MEDICINE & SCIENCE IN TENNIS 19
SELECTED REVIEW OF THE LITERATURE
The Development of Racquet Speed
PROF. BRUCE ELLIOTT, THE SCHOOL OF HUMAN MOVEMENT AND EXERCISE SCIENCE,
THE UNIVERSITY OF WESTERN AUSTRALIA, AUSTRALIA
This article is a modified version of a speed by either reducing the time to move ABOUT THE AUTHOR
chapter from the ITF book ‘Biomechanics a given distance (greater acceleration), or
Bruce Elliott is the Professor of biomechan-
of Advanced Tennis’ 2003 and is increase the distance so that speed can be ics at the School of Human Movement and
published with approval of the editors.2 developed in a more controlled manner. Exercise Science at the University of
Western Australia. He has a passion for
Tennis scientists are continually asked by Research has shown that modern players tennis research and has spent his academic
players to develop techniques that permit generally use the later method by increas- life providing a theoretical basis to tennis
more power, while those involved more ing racket displacement in the backswing stroke production.
with the medical aspect of the game are phase of power strokes. A looped back-
forced to develop better preventative pro- swing further increases the distance the this chain of movements (kinetic chain) is
grams and rehabilitative treatments to racket can develop speed for impact. followed.
meet the demands placed on the body • In a modern serve the racket is ‘away
from movements associated with this addi- from’ and behind the level of the Most coaching texts include a section that
tional power. There are several elements pants/skirt to increase the distance the deals with the flow or summation effect in
that contribute to an increase in racquet racket can move to impact. This further the service action that leads to optimal
and therefore ball speed: enhances performance by putting the racket speed at impact.
muscles around the shoulder on-stretch. Leg drive
1 Elastic energy and muscle pre-tension • It is now common for advanced players +
in the enhancement of racket speed to rotate their racket such that it is paral- Trunk rotation
While neurological factors also play a role lel with the back fence in the one-hand- +
in the enhancement of racket speed in ten- ed backhand, and approximately 45° Upper arm elevation and forward
nis, it is perhaps easiest for coaches to beyond a line pointing at the back-fence movement
attribute the increase in this speed follow- in the forehand stroke, in an attempt to +
ing a preceding stretch of the muscle-ten- increase the distance over which racket Elbow extension
don complex to 1) the recovery of stored speed can be generated. +
elastic energy and 2) a higher active mus- Shoulder internal rotation and forearm
cle state at the start of the drive to the 3 The use of co-ordinated movements pronation
ball. In tennis, where a high racket speed is gen- +
erally required, a number of body Wrist flexion
The theory underlying the use of elastic segments must be co-ordinated if speed
energy in stretch-shorten cycle activities is and accuracy are both to occur. Each 4 The linking of linear and angular
a relatively simple process. During the movement during stroke production may motion
stretch phase the muscles, tendons and be considered as a separate segment, the The linking of forward (linear) and rota-
associated tissues are actually stretched removal of which will detract from the tional (angular) motions are important to
and store energy. Energy is therefore ability to generate racket speed. A multi- the generation of racket speed. In general
stored in tennis during the racket and segment approach to stroke production, terms it is preferable at impact to have the
upper-trunk rotations (backswing) or the norm for all high speed stroking, body moving forward (linear motion).
movement preparation phase (e.g, bending requires a co-ordinated sequence of move- Remember that forward linear movement
of the legs during the split step in a vol- ments if miss-timing/ poor sequencing is of the shoulder is generally created by
ley). On movement reversal, during the not to occur. rotation of the trunk, and upward move-
shortening phase, the stretched muscles ment of this shoulder is created by an
(that are now in a higher active muscle The motion of segments in high-speed ten- effective ‘leg-drive’. In modern tennis an
state than for resting muscles) and tendons nis stroke production is generally ‘open stance’ is used to create more rota-
recoil back to their original shape and in so sequenced in a proximal-to-distal fashion. tional speed (Andy Roddick - forehand)
doing a portion of the stored energy is The only joint movement that has been and a ‘square stance’ is often used to effec-
recovered and assists the movement. shown to occur very late in the for- tively link angular and linear motion.
Research has shown that: wardswing (and therefore not in proximal- Work by Bahamonde and Knudson1 has
• 10-20% additional racket-speed is to-distal sequencing) for the service and shown that similar upper extremity ‘load-
achieved following a stretch-shorten forehand strokes is internal rotation of the ing’ was recorded for open and square
cycle. upper arm. Ben Kibler from the USA has stance forehands.
• Energy is lost if there is more than a presented injury and joint loading data to
brief pause between the stretch and support his view that performance will
shorten phases of a movement. improve and injuries will be reduced, if 5 The role of muscle strength, power and
Approximately 50% of the stored energy endurance
is lost if a pause of 1 s occurs between The relationship between selected physical
the backswing-forwardswing phases of a capacities such as muscle strength/power
stroke (Figure 1). and performance is difficult to quantify in
tennis. Varied relationships have been
2 The distance over which greater racket found between muscle strength and serv-
speed can be developed: ing speed, although research has shown
One of the main reasons of having a back- that a specifically designed exercise pro-
swing is to increase the distance over gram can improve racket speed.
which greater racket speed can be devel- This long-term training together with play
oped during the forwardswing to the ball. leads to muscle imbalances, particularly of
This means a greater stretching of muscle the upper extremity and trunk in
and associated tissues. advanced tennis players. While a muscle
Theoretically speed = distance/ time, Figure 1 Energy loss with incraesed pause imbalance between the right and left fore-
therefore a player may develop racket period arms may be acceptable, an imbalance at
MEDICINE & SCIENCE IN TENNIS 20
Sampras had a more vertical rotation (top-
spin), when compared with the rotation
produced by Rudeski (more topspin/
sidespin). While a similar ball speed was
recorded at the position where the receiv-
er would hit the ball, impact height was
consistently higher for the Sampras serve
(0.1-0.3 m) and the ball had a greater top-
spin rotation by approximately 500 rpm.
This goes part the way to explaining the
difficulty in returning the Sampras serve.
7 The role of equipment design
While modern racket technology has obvi-
ously assisted in the development of
power in the modern game, no attempt
will be made to discuss these because of
word limits on this article
Coaches in reading this chapter will now
realise that there are a number of inter-
related ways to address the question on
how to increase racket speed. More seg-
ments and increased stretch on muscles
and associated tissues are often linked to
Machar Reid (l) and Bruce Elliott
an increase in the level of racket displace-
ment in the backswing and early for-
the shoulder (internal vs. external rotators) racket trajectories are typical for advanced wardswing. Performance in an injury free
or in the trunk for example (left vs. right players preparing for, and then hitting environment will only occur if the body
erector spinae) must be rectified if injury through the impact zone of groundstrokes. has been prepared to meet the loads
is not to follow. An appropriate balance • Flat stroke 25-30° imposed on the body during high-speed
between muscles responsible for the devel- • Topspin stroke 35-45° stroke production.
opment and stopping of high speed seg- • Topspin lob 50-70°
ment rotations will both lead to improved It is this combination of high levels of top- References
performance and a reduced likelihood of spin and ball speed that produce ‘stroke 1 Bahamonde R, Knudson D. Kinetics of
injury. heaviness’. Possibly the best example of the upper extremity in the open and
this phenomena is evident in the return of square stance tennis forehand. J Sci
In powerful tennis strokes, the stability of serve. Yandell2 reported on the service Med Sports 2003;6(1):88-101.
the lower trunk is critical to a successful actions of two of the games ‘big servers’ in 2 Elliott B. The development of racquet
forwardswing and to the prevention of Greg Rusedski and Pete Sampras. speed. In: Biomechanics of advanced
low-back injury. This stability, commonly While they both served at a similar speed tennis. Elliott B, Reid M and Crespo M
referred to as ‘core stability’, involves the ( 190-200 km/hr), impacted the ball at a (eds). London: ITF 2003. ISBN 1 9030
co-ordinated muscle action of the stabilis- similar height ( 2.85 m) and with almost 12 23 2.
ers of the lumbar spine. Precisely timed identical initial rotations ( 2,500 rpm) 3 Yandell J. Comparing the serves of
co-contraction muscles such as transversus there was a key difference in their service Sampras and Rusedski. Tennis Pro
abdominis, lumbar multifidus, the technique. The rotation on the serve hit by 2003; May/June:28-29.
diaphragm and the pelvic floor must
therefore be trained to stabilise the lumbar
spine and provide a base on which other
muscles can effectively contract.
6 ‘Heaviness’ of a stroke
Professional players often refer to the term
‘heaviness of stroking’ as a reason for the
success of a particular player and for that
reason a brief discussion of this is included
as a part of the reason for racket speed at
impact. This ‘heaviness’ will be referred to
as the amount of spin on the ball in com-
bination with its speed just prior to
Ball rotation is created by the movement
and orientation of the racket with respect
to the ball at impact. No purposeful move-
ment between the racket and the ball is BIOMECHANICS OF
possible once impact has occurred, so ADVANCED TENNIS
movement of the racket must follow a pre-
determined path. Upward movement of Bruce Elliott, Machar Reid and
the racket combined with the downward Miguel Crespo (eds)
motion of the ball creates topspin. In Number of pages: 221
groundstokes the forwardswing trajectory London: ITF 2003
tends to be shallow until just before ISBN 1 903013- 23 2
impact, then increases to produce the For orders please visit
desired spin on the ball. The following www.itftennis.com
MEDICINE & SCIENCE IN TENNIS 21
LE Stretching Recommendations for Tennis Players
DUANE KNUDSON, DEPARTMENT OF PHYSICAL EDUCATION AND EXERCISE SCIENCE, CALIFORNIA STATE UNIVERSITY, CHICO,
CHICO, CA 95929-0330, USA
lexibility is an stretching was consistent across skill levels
F important tissue
property that allows
and gender. The lack of a performance
decrement may have been due to move-
ABOUT THE AUTHOR
Duane Knudson, PhD is associate professor
the tennis player to ment complexity or dose-response effects. and associate chair of the Department of
Physical Education and Exercise Science at
freely move with a Another study with longer stretching holds California State University, Chico. He is an
low risk of muscular and a simple throwing task showed signifi- active researcher on tennis biomechanics
injury. Recent cant reductions in overarm throwing per- and is a member of the USTA Sport Science
research on flexibili- formance.11 Committee.
ty and stretching has
shown that the typi- In summary, if tennis players have normal
cal ‘more must be levels of flexibility the warm-up routine an increase in range of motion that could
better’ approach to for tennis should focus on generalised have both positive and negative injury-risk
stretching of tennis movements and strokes of gradually effects depending on the static flexibility
players and coaches is likely incorrect. increasing intensity. Stretching should not status of the person. Theoretically, a
Studies support the theory that both low be performed in the warm-up because hypermobile person increasing their range
and high levels of flexibility may increase there are no documented performance of motion through stretching could result
the risk of injury compared to normal flex- benefits and could very well decrease per- in a less stable joint, greater accessory
ibility.5 Stretching exercises also have a formance. The next section will show that motion, and a higher risk of injury.
variety of effects on the biomechanics of stretching in the warm-up also cannot be
muscle and can adversely affect perform- justified based on the hypothesis of Stretching is also colloquially believed to
ance. This paper will summarise the recent decreasing risk of injury. decrease injury by decreasing the stiffness
research on the effect of stretching on per- of muscle. Unfortunately, this belief seems
formance and injury risk, and conclude by Stretching and Injury Risk to be based on the accurate perception of
making recommendations for stretching in Since flexibility has a complex relationship decreased tension (stress relaxation) at
tennis players. These mass prescription with injury-risk, it should not be surprising specific joint angles and an incorrect
guidelines are intended for uninjured that performing stretching exercises to understanding of the mechanical variable
players since sports medicine professionals increase range of motion do not directly stiffness. Figure 1 provides a schematic of
will likely create individualised stretching result in reductions in injury risk. the rise in passive torque at a joint during
programs for players with injuries or flexi- Unfortunately, the dominant opinion the elongation phase of multiple slow
bility imbalances common in tennis. among most players and coaches is that stretches to the same length. Plotting the
stretching prior to play decreases the risk angular variables of torque and angle
Stretching and Performance of muscular injury. A closer look at the approximate the classic linear load-defor-
One of the largest paradigm shifts in sports association between stretching and injury mation curves of isolated tissues. The
medicine in recent years is the elimination risk is needed on the court and in the behaviour illustrated in Figure 1 has been
of static stretching in warm-up routines for research laboratories. observed in several human studies of a
physical activity. Generalised warm-up variety of muscles, primarily in the lower
movements are critical for increasing tissue The author is aware of no prospective extremity.
temperature, improving performance, and studies of the association between stretch-
increasing the resistance of the tissue to ing (short or long term) and injury risk in The musculotendinous response to passive
injury. Stretching in a warm-up, however, tennis. The largest and best prospective stretch is non-linear, initially with a slow
has considerable research showing substan- studies in this area have shown that rise in torque called the toe region that
tial decreases (5 - 30%) in muscular per- stretching in the warm-up prior to physi- normally corresponds to physiological
formance following stretching.2,4,6 Most of cal training in the military has no12,13,17 or loading for most musculotendinous tissues.
these studies show static stretching minimal effect1 on musculoskeletal injury The stiffness or Young’s Modulus of
decreases high-force muscular perform- rates compared to warm-up alone. One Elasticity (E) of the muscle group is the
ance,10 although there are also studies acute and long-term effect of stretching is rate of increase (slope) in passive torque in
showing this effect in lower load move- the elastic (linear) region of the graph. If
ments like jumping and throwing.3, 11 the tissue were elongated further the
The effect appears to be equally related to torque would increase and eventually
decreased muscular contractile force and reach the elastic limit where permanent
activation,2 and can last up to an hour.4 It damage (plastic region) to the tissue and
is interesting to note that the performance would occur. Note that the short-term
decrements of stretching before activity effect of stretching does not affect the
have been consistently observed when stiffness of the muscle group (E), although
most subjects would be expecting superior there would be less passive resistance for a
performance (reverse placebo effect) fol- given joint angle. The studies on the long-
lowing stretching. term effects of stretching also show no sig-
nificant effects on muscular stiffness.7
The question arises if stretching induced
decrements also occur in high-speed These measures of the passive stiffness of
movements like tennis strokes. A recent muscle groups are different than the stiff-
study examined if typical static stretching ness measured in during muscle activation.
done by tennis players in warm-ups Figure 1. Schematic of a torque-joint angle Clinical observations and research show
decreased service performance.9 First serve plot during for repeated passive stretches of a many muscular injuries tend to occur dur-
speed and service percentage of diverse muscle group. Stress relaxation makes the ing eccentric (lengthening) contractions.
sample of players were measured following passive torque at a given joint angle in subse- While some studies have measured the
a traditional warm-up and then following a quent stretches (thin line) less than the first stiffness of muscle groups in active condi-
stretching program. No significant differ- stretch (thick line). The stiffness (E) of the tions, it is unclear how the passive stiffness
ences in serve speed or percentage were muscle group in these stretches, however, is and active stiffness of muscles are related.
observed and this lack of an effect of not different. In summary, there is little clinical or basic
MEDICINE & SCIENCE IN TENNIS 22
science evidence to show that stretching imbalances related to the repetitive 7 Knudson D. Stretching during the warm-up: do
we have enough evidence? J Phys Ed Rec
prior to physical activity like tennis motions of tennis play.14,16 Potential trou- Dance 1999;70(7):24-27, 51.
decreases the risk of muscular injury.7,15,17 ble areas that should be routinely 8 Knudson D, Magnusson P, and McHugh M.
Most studies show that stretching can stretched in tennis players are the ham- Current issues in flexibility fitness. Phys Fit Res
increase range of motion but will have a strings, low back, calf, hip adductors and Dig 2000;3(10):1-8.
negligible effect on the stiffness of internal rotators, shoulder internal rota- 9 Knudson D, Noffal G, Bahamonde R, Bauer J,
and Blackwell J. Stretching has no effect on ten-
muscle.8 This combined with the epidemi- tors, and hip flexors. Based on the biome- nis serve performance. J Strength Cond Res (in
ological literature suggests that the com- chanical and clinical studies of stretching, press).
mon belief that stretching prior to activity Knudson8 has recommended that 4-5 stat- 10 Nelson AG, Guillory IK, Cornwell A, and
reduces the risk of injury is likely false. ic or PNF stretches be performed for each Kokkonen J. Inhibition of maximal voluntary iso-
kinetic torque production following stretching is
Stretching following physical activity, muscle group. Each stretch should be held velocity specific. J Strength Cond Res
however, may be appropriate to maintain at ‘with low levels of force’ for 15-30 sec- 2001;15:241-246.
normal levels of range of motion. More onds. These general guidelines are appro- 11 Noffal G, and Knudson D. Effect of stretching
prospective studies are needed to docu- priate for most tennis players. on throwing speed and isokinetic shoulder
ment the normal or desirable ranges of torques (submitted).
12 Pope RP, Herbert RD, and Kirwan JD. Effects
motion that are associated with lower risks References of flexibility and stretching on injury risk in
of muscular injury, and on the effect of 1 Amako M, Oda T, Masuoka K, Yokoi H, and army recruits. Aust J Physiother 1998; 44:165-
musculotendinous stiffness on risk of vari- Campisi P. Effect of static stretching on preven- 172.
tion of injuries for military recruits. Military Med 13 Pope RP, Herbert RD, Kirwan JD, and Graham
ous injuries. 2003; 168:442-446. BJ. A randomized trial of pre-exercise stretch-
2 Avela J, Kyrolainen H, and Komi PV. Altered ing for prevention of lower-limb injury. Med
Stretching for Tennis Players reflex sensitivity after repeated and prolonged Sci Sports Exerc 2000;32:271-277.
Although there is an incomplete under- passive muscle stretching. J Appl Physiol 14 Roetert EP, Ellenbecker TS, and Brown SW.
standing of the effects of stretching on per- 3 Cornwell A, Nelson AG, Heise GD, and
Shoulder internal and external range of motion
formance and injury risk, the data can be in nationally ranked junior tennis players. J
Sidaway B. Acute effects of passive muscle Strength Cond Res 2000;14:140-143.
used to suggest general guidelines appro- stretching on vertical jump performance. J Hum 15 Shrier I. Stretching before exercise does not
priate for tennis players. Most tennis play- Mov Stud 2001;40:307-324. reduce the risk of local muscle injury: a critical
ers should perform static stretching exer- 4 Fowles JR, Sale DG, and MacDougall JD. review of the clinical and basic science litera-
Reduced strength after passive stretch of the ture. Clin J Sports Med 1999; 9:221-227.
cises in the cool-down following matches human plantar flexors. J Appl Physiol 2000; 16 Vad VB, Gebeh A, Dines D, Altchek D, and
or conditioning. The goal should be to 89:1179-1188. Norris B. Hip and shoulder internal rotation
maintain normal ranges of motion for all 5 Jones BH and Knapik JJ. Physical training and range of motion deficits in professional tennis
the major muscle groups. Sports medicine exercise-related injuries. Sports Med players. J Sci Med Sport 2003;6:71-75.
professionals can assist players by monitor- 6 Kokkonen J, Nelson AG, and Cornwell A. Acute
17 Weldon SM, and Hill RH. The efficacy of
ing ranges of motion for problem joints, stretching for prevention of exercise-related
muscle stretching inhibits maximal strength per- injury: a systematic review of the literature.
especially in the joints with common formance. Res Q Exerc Sport 1998;69:411-415. Man Ther 2003; 8:141-150.
ARCH Viscosupplementation not effective for the treatment of
posttraumatic osteoarthritis of the elbow
RICHARD W. VAN BRAKEL, MD, AND DENISE EYGENDAAL, MD, DEPT. OF ORTHOPAEDIC SURGERY, SINT MAARTENSKLINIEK,
PO BOX 9011, 6500 GM NIJMEGEN, THE NETHERLANDS. TEL +31 24-3659293. E-MAIL: D.EYGENDAAL@MAARTENSKLINIEK.NL
he treatment of popular modality for safe and effective
osteoarthritis of the
treatment of osteoarthritis of the knee. It
consists of a series of intra-articular injec-
ABOUT THE AUTHORS
Richard van Brakel is Registrar at the
Department of Orthopaedic Surgery in the
elbow in young tions with hyaluronic acid or its deriva- Sint Maartenskliniek, a specialised hospital
patients remains a tives. Hyaluronic acid is an endogenous for orthopaedic surgery in the Netherlands.
challenge. Due to proteoglycan which can be found in syn-
Denise Eygendaal is orthopaedic surgeon in
pain and functional ovial fluid and also serves as a backbone the Sint Maartenskliniek and is specialised
limitation of the for proteoglycans in cartilage matrix. Being in Upper Limb Surgery and Sports
joint it can cause a major constituent of synovial fluid, it has Medicine.
great impairment in visco-elastic properties by which it can act
every day function as a lubricant during slow movement and
and sports activities. as a shock absorber during rapid move- viscosupplementation. Other parameters
In order to reduce ment. were not influenced by treatment with vis-
pain and hence maintain or restore func- cosupplementation at any time. Systemic
tion, the current conservative options of In this prospective cohort study, we evalu- or local adverse effects did not occur.
treatment are analgetics and intra-articular ated the effect and safety of viscosupple-
injection of corticosteroids. Both options mentation in 20 elbows with posttraumat- Because the use of viscosupplementation
have important limitations. Intra-articular ic osteoarthritis of 19 patients (9 male, 10 for the treatment of posttraumatic
injection with corticosteroids are only indi- female, average age 47,1 years, SD: 15,8 osteoarthritis of the elbow provides only
cated for patients with synovitis and joint years). Three injections with sodium slight (but not significant) short-term pain
effusion. They provide quick relief but hyaluronate were given within four weeks relief while other parameters were not
only of short duration and can cause ‘flare- with regular intervals. Evaluation took modified, we believe that viscosupplemen-
up’ of the joint and systemic side-effects. place just before the first injection as well tation is not suitable for this indication.
Whether intra-articular injection with cor- as after three and six months and consisted
ticosteroids may induce extra deterioration of the Elbow Function Assessment Score, The deformity of the joint as a result of
of cartilage remains uncertain due to the the Functional Rating Index by Broberg trauma and the possibility that the syn-
fact that it has not been studied in and Morrey and the Modified Andrews ovial fluid of posttraumatic osteoarthritic
humans. Experimental data from animal Elbow Scoring System. Pain was also joint is superior to synovial fluid of joints
studies are contradictory. assessed by means of Visual Analogue with degenerative osteoarthritis regarding
Scales. rheological properties may explain the
In recent years, intra-articular viscosupple- Only pain showed a slight (but not signifi- ineffectiveness of intra-articular injections
mentation has become an increasingly cant) decrease three months after starting with sodium hyaluronate.
MEDICINE & SCIENCE IN TENNIS 23
WTA Tour Age Eligibility and Professional Development
Ten Year Review
representatives of various facets of the
PHOTO CREDIT GETTY IMAGES
2004 marks ten years since the WTA
Tour presented its ground- breaking tennis community: former players,
investigation into the entry age of agents, coaches, the media, tennis manu-
women players on the WTA Tour that facturers, the ATP, the Grand Slam com-
resulted in the formation of the Profes- mittee, the ITF Women’s Department,
sional Development Department and the ITF Juniors’ Department, Board
programs and the Age Eligibility Rule. members representing the players and
tournaments, and a research consultant.
As part of the WTA Tour’s ongoing com- This ‘steering committee’ provides a
mitment to the career fulfillment and wealth of information, expertise and
longevity of its players, the WTA Tour is varied perspectives to the review process.
commencing a ten-year review of the
Age Eligibility Rule and the Professional The purpose of the Los Angeles meeting
Development Department programs. was to facilitate input and ideas from
The current Age Eligibility Panel is con- each facet of the tennis world on what
ducting this review. The Panel consists of issues should be investigated and the
an international group of independent methods of researching and analysing the
group of sports sciences and medicine issues during the 2004 Professional
specialists, all with expertise and experi- Development review.
ence in elite tennis and many of whom
are members of the STMS. Additionally the worldwide tennis com-
munity shared ideas and interest in creat-
• Carol L. Otis, M.D., FACSM (USA), ing programs to ensure the health and
Chairperson, expert in internal medi- During the WTA Tour season ending welfare of young promising professional
cine and primary care sports medicine Championships in Los Angeles, the Age players. The Age Eligibility Panel will
with an emphasis on women athletes; Eligibility Panel conducted a preliminary formulate the 2004 review process,
• Babette Pluim, M.D., Ph.D. (The meeting, via teleconference and in per- which will include surveys, in-person tes-
Netherlands), expertise in sports son, with a select group of tennis con- timonials and extensive research and data
cardiology, exercise physiology and stituents regarding the proposed review. analysis. The expected completion date
sports medicine; The constituents included international for this review is August 2004.
• Ann Quinn, Ph.D. (Australia), expert
in sport psychology and fitness training, CALL FOR SUBMISSIONS
elite coaching and coach education;
For the WTA Tour Age Eligibility and Professional Development Ten Year Review
• Miguel Crespo, Ph.D. (Spain), expert in
tennis psychology and elite coaching; STMS members are asked to submit any relevant articles for the purposes of assisting the
Age Eligibility Panel of the WTA Tour in the collection of data for the literature review.
• Jim Loehr, Ed.D., FACSM (USA), Submissions can include articles from peer-reviewed journals, presentations from
sports psychologist with an emphasis conferences, and any current research that STMS members are or have undertaken.
on tennis; Relevant material from the last ten years (1993-2003) in the areas of sport sciences and
medicine in relation to the physical, mental and emotional effects of training and competi-
• Paul Roetert, Ph.D., FACSM (USA),
tion for tennis players from juniors through elite level is requested.
kinesiologist with an emphasis on
tennis training; Submissions are requested from all disciplines: sports medicine; sports psychology; sports
• Kathleen Stroia, M.S., P.T., A.T.,C. sociology; exercise physiology; physiotherapy; nutrition; strength and conditioning; bio-
(USA), expertise in athletic training mechanics; coaching; equipment /technology sciences; and any other relevant disciplines.
and physical therapy with an emphasis
The Age Eligibility Panel aims to complete a very comprehensive multidisciplinary literature
on women’s professional tennis; review as a critical component of the 2004 Age Eligibility and Professional Development
• Peter Terry, Ph.D. (Australia), sports ten-year review.
psychologist with an emphasis on
tennis; Please submit articles to:
• Tandy O’Donoghue (Non voting legal Associate Vice President, Sports Science and Medicine & professional Development
advisor – USA), WTA Tour Chief Departments,
Legal Officer; One Progress Plaza, Suite 1500 – St Petersburg, Florida, 33701
Phone: 1 727 895 5000 – E-mail: firstname.lastname@example.org
• Bart McGuire (Non voting special
advisor- USA), visiting professor of law Please search your libraries and submit relevant articles to assist the Age Eligibility Panel
Northwestern School of Law, Lewis and the WTA Tour in this very important review process. Thank you in anticipation!
and Clark College Deadline is 5 February, 2004
The newsletter Medicine and Science in Tennis is endorsed by:
MEDICINE & SCIENCE IN TENNIS 24