Eccentric and Concentric Force-Velocity Relationships of the

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					Eccentric and Concentric Force-Velocity
Relationships of the Quadriceps
Femoris Muscle
Nancy M. Cress, MS, PT'
Kristin S. Peters, MS, PT2
\die M. Chandler, MS, PT3

             unctional activity involves           Most functional activities utilize all three types of muscle contraction. The purpose of this
             patterns of concentric, ec-   study was to examine concentric and eccentric force-velocity relationships of the knee extensors of
             centric, and isometric        30 young, healthy females at seven velocities between 30 and 2lO0/secusing the Kinetic Communi-
             contractions. All compo-      cator. The average force produced by the quadriceps during three concentric and three eccentric
             nents of motion, such as      contractions was calculated at each velocity. The force-velocity relationships were graphed and
initiation, force production, coordi-      analyzed using linear regression techniques. Results showed that the mean slope of the combined
nation of muscle groups, change of         linear regression lines of concentric data was -0.55, which is significantly different from a zero
direction, and velocity, a r e necessary   slope. This indicates that concentric force of the knee extensors decreases as velocity increases. The
for function and a r e addressed in the    mean slope of the combined linear regression lines of the eccentric data was -0.04, indicating no
training of an athlete and the reha-       significant change in eccentric force with an increase in velocity. It appears, therefore, that in the
bilitation of a patient. Research has      knee extensors of healthy, young females, concentric force decreases as velocity increases to 210°/
shown that a torque produced               sec, while eccentric force remains the same. Both concentric and eccentric work are often empha-
against a load is related t o the veloc-   sized in strength training programs. It is, therefore, important for professionals involved in the
ity a t which the movement occurs. In      rehabilitation or training of patients and athletes to be aware of differences between eccentric and
concentric contractions, force de-         concentric force-velocity relationships.
creases as velocity increases. T h e
                                           Key Words: quadriceps fernoris, force-velocity relationships, concentric/eccentric
force-velocity relationship of eccen-
tric action, however, has not been es-     ' StaNphysical therapist, Duke University Medical Center, Durham, NC. At the time this research was con-
                                           ducted, Ms. Cress was a student in the Craduate Program in Physical Therapy at Duke University.
tablished. Some of the variation in        Staff physical therapist, University of Wisconsin Hospitals and Clinics, Madison, WI. At the time this research
findings may be d u e t o differences      was conducted, Ms. Peters was a student in the Craduate Program in Physical Therapy at Duke University.
among researchers in test protocols,       'Assistant clinical professor, Craduate Program in Physical Therapy, Duke University, Durham, NC
instrumentation, muscle groups
tested, measurements taken, and            centric contractions of the lower ex-                      force-velocity curve may be due, in
types of subjects examined.                tremity. This finding has been dem-                        part, to methodological differences
                                           onstrated across a wide velocity spec-                     in the measurement of force. T h a t
LITERATURE REVIEW                          trum (0-330°/sec) and in a variety                         is, the authors recorded peak torque
                                           of populations (3,5,10,12,19,22).                          values achieved a t a set angle of knee
     In numerous studies that have         O n e report that contrasted other                         extension rather than recording
used isokinetic dynamometers t o ex-       findings was that of Perrine and Ed-                       peak torque values obtained
amine force-velocity relationships,        gerton (1 7). They found an increase                       throughout the range of motion.
authors consistently report that the       in concentric peak torque of the                           T h e angle at which minimum torque
force of concentric upper extremity        knee extensors when velocity in-                           is achieved in the knee extensors has
muscle contractions decreases as ve-       creased from 4 5 t o 96"/sec, while a t                    since been shown to change a t differ-
locity increases t o 2 10°/sec (6,12-      velocities above 96"/sec, the usual                        ent velocities (16).
14). Investigators have shown similar      decline in peak torque was noted.                               T h e force-velocity relationship
force-velocity relationships for con-      T h e differences in this concentric                       of eccentric action has also been ex-

                                                                                                          Volume 16 Number 2 August 1992 JOSPT
                                                                                                    RESEARCH S T U D Y

amined. In studies performed on u p         urements recorded, and types of sub-        Ages ranged from 22 to 32 years
per extremity muscles, most authors        jects examined.                              (mean age = 2 5 years, S.D. = 2.6).
agree that the force of eccentric                  Because there a r e many variables   Master athletes and weight trainers
muscle action increases as velocity in-     that may affect force measurements,         were excluded from the study, as
creases to 210°/sec (1,13,14,21).           it is necessary t o develop experimen-      were individuals with knee pathol-
Griffen reported that eccentric el-         tal protocols that control as many of       ogy, cardiovascular, neuromuscular,
bow flexor peak torque increases as         these variables as possible. Isokinetic     o r musculoskeletal disease. All par-
velocity increases between 0 and           dynamometers that can measure                ticipants gave informed consent
 120°/sec but then decreases between        both concentric and eccentric force         prior t o testing.
 120 and 21 OO/sec (6).                    allow investigators t o examine both
     Results from lower extremity          concentric and eccentric force-veloc-        Instrumentation
force-velocity studies of eccentric iso-    ity relationships of specific muscle
kinetic action have been less consist-      groups in a homogeneous population              T h e Kinetic Communicator
ent. Eloranta and Komi used eight           using the same measurement device.          (Kin-Com 11, Chattex Corp., Chatta-
linear velocities between 0.12 and          Data derived from experimental pro-         nooga, T N 37405) is a hydraulically
0.97 m/sec on a specially con-              tocols using such devices may ulti-         driven dynamometer capable of
structed dynamometer t o examine            mately clarify the similarities and dif-    measuring both concentric and ec-
the eccentric force-velocity relation-      ferences between concentric and ec-         centric force produced a t speeds u p
ship of the quadriceps (3). T h e au-       centric force-velocity relationships of     to 210°/sec. Through feedback
thors found n o significant change in       several muscle groups. Therapists           loops, the instrument controls the
eccentric peak force as velocity in-        and trainers often incorporate both         range of motion and velocity of the
creased. Hageman e t al (7) measured        concentric and eccentric work into          lever arm and registers the amount
the absolute peak torque during ec-         rehabilitation and weight training          of force exerted by the user.
centric contractions of quadriceps          programs in order t o improve func-             Farrell and Richards (4) have
and hamstring muscles of normal             tional performance of patients and          demonstrated that the Kin-Com is
volunteers on the Kinetic Communi-          athletes. It is, therefore, important       mechanically reliable and suitable for
cator a t 3 0 and 180°/sec. No signifi-     t o understand differences between          research needs (ICC = .948 t o 999).
cant difference in peak torque was          eccentric and concentric force-veloc-       Good clinical reliability of the Kin-
found between the two velocities in         ity relationships when designing            Com has also been established, with
males. In females, however, an in-          strengthening programs.                     ICCs ranging from .47 to .95 for ec-
crease in eccentric hamstring torque              T h e purpose of this study was t o   centric and concentric torque and
was observed as velocity increased.         examine the eccentric and concen-           force measures (8,9,18,2O).
Knee extensors of normal male vol-          tric force-velocity relationship of the
unteers tested eccentrically a t 60,        right quadriceps femoris muscle             Procedure
 120, and 180°/sec on the Kinetic           from 3 0 t o 2 1OO/sec on the Kinetic
Communicator by Chandler and                Communicator in healthy young                     T h e Kin-Com I1 was used to
Duncan showed a slight but signifi-         women. It was hypothesized that:            measure the average force produced
cant decrease in average force with             I ) the force of concentric contrac-    during maximum voluntary concen-
increased velocity (2).                             tions produced by the knee ex-      tric and eccentric contractions of the
    In summary, during concentric                   tensors would significantly de-     right quadriceps femoris muscle
contractions of both the upper and                  crease as velocity of contraction   group a t test velocities of 30, 60, 90,
lower extremities, force decreases as               increased, and                       120, 150, 180, and 210°/sec. T h e
velocity increases. T h e eccentric            2) the force of eccentric contrac-       order of the velocities was randomly
force-velocity relationship, however,               tions produced by the knee ex-      assigned. In addition, the mode of
has not been consistently described.                tensors would not change as ve-     contraction, concentric o r eccentric,
In the upper extremity, it generally                locity of contraction increased.     t o be performed first was randomly
appears that eccentric force increases                                                   selected. All testing took place in the
as velocity increases. However, in the     METHODS                                       Physical Therapy Department at
lower extremity, eccentric force may                                                     Duke University Medical Center.
increase, decrease, o r stay the same      Subjects                                           Subjects were seated on the Kin-
as velocity increases. Some of the in-                                                   Com with hips and knees flexed to
consistency in results may be ac-              Thirty female volunteers from             90". T h e posterior aspect of the sub-
counted for by differences in testing      the Duke University Graduate                 ject's right knee cleared the seat by
protocols, instrumentation, muscle         School and from the Durham, NC                 112 t o 1 in. T h e axis of knee joint
groups tested, force o r torque meas-      community participated in this study.         rotation was aligned with the axis of

IOSPT Volume 16 Number 2 August 1992
-- R C H
RESEA             STUDY

 rotation of the lever arm on the Kin-      tigue during the testing procedure.                  RESULTS
 Com. T h e pelvis was stabilized by a      Each maximal effort was separated
 V l r @ strap placed over the ante-
   eco '                                    by a 5-second pause. Strong verbal                        T h e mean slope of the combined
 rior superior iliac spines. A second       encouragement was given during                       regression lines of the concentric
 strap was used to stabilize the distal     maximal contractions. After a 2-min-                 data was -0.55 (SD = .25) and was
 right thigh. T h e pad on the lever        ute rest, the sequence of warm-up                    found to be significantly different
 arm of the Kin-Com was attached            contractions followed by test con-                   from zero ( p C .01) (Figure 2). A
 with a Velcro strap to the anterior        tractions was performed at the next                  mean slope of -0.04 (SD = .34) was
 aspect of the distal tibia two finger      randomly selected velocity.                          determined for the combined eccen-
 widths proximal to the malleolli. A                                                             tric regression lines (Figure 3). This
 total range of motion of 85" was set                                                            slope was not found to be signifi-
 by asking the subject to extend the        Data Collection and Analysis                         cantly different from zero.
 knee to 5" and then to flex the knee
 to 90" as monitored by the Kin-                 T h e Kin-Com computer deter-                   DISCUSSION
 Com's computer. Subjects were              mined the average force in N gener-
 asked not to hold on to the Kin-Com        ated during the three maximal con-                        T h e negative slope of the com-
 with their hands. One researcher           centric contractions and calculated                  bined regression lines for the con-
 consistently aligned, instructed, and      the arithmetical mean of the three                   centric data indicates that concentric
 motivated the subjects, while the          average force values. T h e same force               force decreases as velocity increases
 other attended to the computer and         data were collected for the eccentric                to 210°/sec (Figure 2). This is con-
 the collection of data.                    trials. In addition, the computer pro-               sistent with the study hypothesis as
       T o become familiar with the         duced plottings of the average force                 well as with previous research of
 Kin-Com and alternating concentric         produced throughout the range (Fig-                  concentric force-velocity relation-
 and eccentric contractions, each sub-      ure 1).                                              ships in both the upper and lower
ject was allowed 10 submaximal con-              Linear regression techniques                    extremities (2,3,4,6,10,12-
 tractions in each mode at 105"/sec,        were used to determine the slopes of                 15,17,19,22,23). Klopfer and Greij
 followed by a 90-second rest. A mid-       the regression lines for each subject's              present a possible explanation, sug-
 dle range speed of 105"/sec was cho-       concentric and eccentric data. A                     gesting that faster speeds allow less
 sen for the initial practice session be-   mean slope for all the concentric                    time in which to recruit motor units
 cause it was believed to be in a more      data and a mean slope for all the                    for a strong contraction (1 !). There-
 comfortable exercise velocity range        eccentric data were calculated. A                    fore, as velocity increases, fewer
 than either the lower speeds (30-          nonparametric equivalent to the t-                   muscle fibers contract and force de-
 90°/sec) o r the higher speeds (180-       test was used to determine if the                    creases.
 2 1OO/sec).In addition, the investiga-     mean slope in each case was differ-                       T h e finding that the concentric
 tors believed that 105"/sec, which         ent from the slope of a horizontal                   force-velocity relationship appears
 was not one of the "testing" veloci-       line, o r zero.                                      linear has not been reported previ-
 ties, would allow the subjects to be-
 come used to the eccentric mode of
 exercise without letting them get ad-                                                         Disp. No.          1          2
 ditional practice at one of the test                                   NUMERIC
 velocities. Then, prior to actual data                                                       Type            +CON          E C h
 collection at each velocity, the sub-                                                        Accepted           3           3
ject warmed up with two submaxi-
                                                                                              Veloclty           86         87
 ma1 contractions followed by one
 maximal contraction in each mode at
the specified velocity. This was fol-
 lowed by a 60-second rest period.
T h e actual test from which average
force data were collected involved
                                                                                              Fom               285         464
three maximal contractions in each
mode at the specified velocity. Three
 maximal contractions at each test ve-                                                        Angle                     -
                                                                                                           Average, 5(L) 90(R) deg
 locity were believed to be represent-
 ative of the subject's maximal effort      FIGURE 1. Example of data produced by the Kin-Com computer showing the average force produced
 without causing undue muscle fa-           concentrically and eccentrically by one subject at 90e/sec.

                                                                                                      Volume 16 Number 2 August 1992 JOSPT
ously in the literature. This incon-                      tively, on the Cybex 11. It is possible              esis that there is n o significant
sistency may be explained by the fact                     that concentric force generated over                 change in eccentric force as velocity
 that a relatively narrow velocity spec-                  a wider velocity range might result                  increases to 2 1OO/sec.
 trum, 3 0 t o 210°/sec, was used in                      in a logarithmic rather than linear                       An explanation for the mainte-
this study. Ingemann-Hanson and                           force-velocity curve (22).                           nance of eccentric muscle force with
 Halkjaer-Kristenson (1 0) tested sub-                         T h e slope of the combined                     increasing velocity in the lower ex-
jects on a modified Orthotron using                       regression lines for the eccentric                   tremity can be found in the physiol-
a wider velocity range from 3 0 t o                       data is essentially zero (Figure 3). No              ogy of muscle. A muscle has both
 360°/sec. At the higher velocities,                      trends toward either an increasing                   contractile and elastic components.
 they noted a "leveling off" of con-                      slope o r a decreasing slope seem t o                Active lengthening of muscle is, in
centric force. This finding is s u p                      emerge from the data. In fact, of the                part, controlled by the passive resist-
ported by the work of Wyatt e t al                        3 0 individual regression lines, half                ance to stretch of the elastic compo-
 (23) and Montgomery e t al (1 5), who                    had a slightly positive slope and half               nents, whereas shortening is con-
 tested force produced a t velocities                     had a slightly negative slope. This                  trolled solely by the contractile ele-
 up t o 300 and 330°/sec, respec-                         finding is consistent with the hypoth-               ments. Thus, the elastic components
                                                                                                               contribute t o force produced during
                                                                                                               an eccentric contraction but not dur-
                                           Concentric Contraction                                              ing a concentric contraction. T h e
                    400]                                                                        1              physiologic behavior of the elastic
                                                                                                               elements may account for differ-
                                                                                                               ences in eccentric and concentric
                                                                                                               force production as velocity in-
                                                                                                                    T h e results of the eccentric data
                                                                                                               from this study are comparable t o
                                                                                                               those of Eloranta and Komi (3) and
                                                                                                               Hageman et al(7), who found no
                                                                                                               change in eccentric peak force and
                                                                                                               peak torque, respectively, as velocity
                                                                                                               increased. Chandler and Duncan
                                                                                                               demonstrated a slight decrease in ec-
                                                                                                               centric quadriceps muscle force with
                                          Velocity (Degreesfsecond)                                            increasing velocities on the Kin-
                                                                                                               Com, but only examined a narrow
FIGURE 2. Average concentric force of the quadriceps plotted against velocity of contraction. The line drawn   velocity spectrum of 6 0 t o 180°/sec
here represents the mean slope of the regression lines for all 30 subjects.
                                                                                                                    Eccentric force-velocity relation-
                                             Eccentric Contraction                                             ships for the upper extremity appear
                                                                                                               to be different from those reported
                                                                                                               for the lower extremity. In the up-
                                                                                                               per extremity, a slight positive slope
                                                                                                               with eccentric force increasing as ve-
                                                                                                               locity increases has been shown
                                                                                                               (1.1 3,l4,2 1). Differences in the ec-
                                                                                                               centric force-velocity relationships
                                                                                                               between upper and lower extremities
                                                                                                               could be explained by functional dif-
                                                                                                               ferences between the two muscle
                                                                                                               groups. T h e lower extremity muscles
                      1504                                   I                                 I               contract eccentrically for many func-
                                  30      60       90       120     150      180     210                       tional activities. This is especially
                                                                                                               true of the knee extensors during
                                         Velocity (DegreedSecond)
                                                                                                               walking and running. Compared to
FIGURE 3. Average eccentric force of the quadriceps plotted against velocity of contraction. The line drawn    the lower extremity muscles, the up-
here represents the mean slope of the regression lines for all 30 subjects.                                    per extremity muscles may not per-

JOSPT* Volume 16 * Number 2 * August 1992
R E S E A R C H S T U D .Y.    ..   -,.-.-...--.-,..-..-----   .-,   - ---------.-..-.-.,-.---.--- -   --..--   -----..--...--------

 form as many functional tasks involv-         spectrum. These findings are consist-                        the human quadriceps muscles. Scand
 ing eccentric contractions o r tasks          ent with previous reports in the liter-                      I Rehabil Med 11:85-89, 1979
 that require heavy o r high velocity          ature for all concentric force-velocity             1 1. Klopfer DA, Creig SD: Examining
                                                                                                         quadriceps/hamstringsperformance at
 loading. Therefore, it is possible that       relationships and for eccentric force-                    high velocity isokinetics in untrained
 differences in the eccentric force-           velocity relationships of the knee ex-                    subjects. I Orthop Sports Phys Ther
 velocity relationships of upper and           tensors.                                                   1O(7):18-22, 1988
 lower extremity muscle groups may                                                     JOSPT
                                                                                                   12. Knapik 11, Ramos MU: lsokinetic and
 be a result of differences in their                                                                     isometric torque relationships in hu-
 functional behavior.                                                                                    man body. Arch Phys Med Rehabil
                                                                                                         6 1:64-67, 1980
     Factors that may have affected
                                               REFERENCES                                          13. Komi PV: Measurement of the force-
 the results of this study should be                                                                     velocitv relations hi^ in human muscle
considered. First, fatigue must al-                 Asmussen E, Hansen 0, Lammert 0 :                    under concentric and eccentric con-
ways be a concern in studies involv-                  The relation between isometric and                 tractions. In: joki E (ed), Medicine and
                                                     dynamic muscle strength in man.                    Sport, pp 224-229. Basel, Switzerland:
ing multiple contractions. To mini-                  Communications from the Testing and                S. Karger AC, 1973
mize potential confounding effects                   Observation Institute of the Danish          14. Komi PV: Relationship between mus-
of fatigue, speeds were randomly as-                 National Association for Infantile Pa-             cle tension, EMG, and velocity of con-
signed for each individual and a 2-                  ralysis 20, 1965                                    tractions under concentric and eccen-
minute rest period was consistently                  Chandler lM, Duncan PW: Eccentric                  tric work. In: Desmedt l E (ed), New
                                                     vs. concentric force-velocity relation-            Developments in EMG and Clinical
provided between tests a t each veloc-               ships of the quadriceps femoris mus-               Neurophysiology, pp 596-606. Basel,
ity. In addition, a few subjects com-                cle. Unpublished manuscript. Duke                  Switzerland: National Zeiting AC,
plained of discomfort caused by the                  University, Durham, NC, 1987                        1973
shin pad. Such discomfort may have                   Eloranta V, Komi PV: Function of the         15. Montgomery LC, Douglass LW, Deus-
inhibited their ability t o produce a                quadriceps femoris muscle under max-               ter PA: Reliability of an isokinetic test
maximal contraction consistently.                    imal concentric and eccentric contrac-             of muscle strength and endurance. I
                                                     tions. Electromyogr Clin Neurophysiol              Orthop Sports Phys Ther 70(8):315-
Because the data were remarkably                     20: 159- 1 74, 1980                                322, 7989
consistent within individuals, how-                  Farrell M, Richards /C: Analysis of the      16. Osternig LR: Optimal isokinetic loads
ever, it appears that neither pain nor               reliability and validity of the Kinetic            and velocities producing muscular
fatigue were major confounding fac-                  Communicator exercise device. Med                  power in human subjects. Arch Phys
                                                     Sci Sports Exerc 18(1):44-49, 1986                 Med Rehabil56: 152- 155, 1975
tors in this study.                                 Froese EA, Houston ME: Torque-veloc-          17. Perrine 11, Edgerton VR: Muscle force-
     Further investigation of this phe-              ity characteristics and muscle fiber               velocity and power-velocity relation-
nomenon might include similar test-                  type in human vastus lateralis. 1 Appl             ships under isokinetic loading. Med Sci
ing over a wider velocity spectrum,                  Physiol59(2):309-3 14, 1985                        Sports 10:150- 766, 1978
especially at higher velocities, of                 Criffen IW: Differences in elbow flex-        18. Scudder CN: Torque curves produced
                                                     ion torque measured concentrically,                at the knee during isometric and iso-
both upper and lower extremity                      eccentrically, and isometrically. Phys              kinetic exercise. Arch Phys Med Re-
muscle groups. Comparisons among                     Ther 67(8):7 205- 1208, 1987                       habil6 1:68-73, 1980
normal subjects, elite athletes, and                Hageman PA, Cillaspie DM, Hall LD:            19. Thorstensson A, Crimby C, Karlsson I:
patients may further elucidate phys-                 Effects of speed and limb dominance                Force-velocity relations and fiber com-
iological mechanisms underlying                     on eccentric and concentric isokinetic              position in human knee extensor mus-
                                                    testing of the knee. 1 Orthop Sports                cles. / Appl Physiol40: 12- 16, 7 976
concentric and eccentric force-                     Phys Ther 1O(2):59-65, 1988                   20. Tredinnick TI, Duncan PW: Reliability
velocity relationships.                             Harding B, Black T, Bruulsema A, Max-               of measurements of concentric and ec-
                                                    well B, Stratford P: Reliability of a re-           centric isokinetic loading. Phys Ther
                                                    ciprocal test protocol performed on                 68(5):656-659, 1988
                                                    the Kinetic Communicator: An isoki-           21. Walmsley RP, Pearson N, Stymeist P:
CONCLUSION                                          netic test of knee extensor and flexor              Eccentric wrist extensor contractions
                                                    strength. I Orthop Sports Phys Ther                 and the force velocity relationship in
     Results of this study demonstrate               1O(6):Z18-223, 1988                                muscle. I Orthop Sports Phys Ther
                                                    Highgenboten CL, lackson AW, Meske                  8(6):288-293, 1986
that concentric force of the quadri-                NB: Concentric and eccentric torque           22. Wilkie DR: The relation between force
ceps decreases when velocity of                     comparisons for knee extension and                  and velocity in human muscle. Phys-
movement increases from 30 t o                      flexion in young adult males and fe-                iol 1 10:249-280, 1950
2 10 "/set on the Kin-Comdynamo-                    males using the Kinetic Communica-            23. Wyatt MP, Edwards AM: Comparison
                                                    tor. Am I Sports Med 16(3):234-237,                 of quadriceps and hamstring torque
meter. Eccentric force production,                   1988                                               values during isokinetic exercise. / Or-
on the other hand, appears t o re-                  Ingemann-Hansen T, Halkjaer-Kristen-                thop Sports Phys Ther 3(2):48-56,
main constant over the same velocity                sen I: Force-velocity relationships in              1981

                                                                                                         Volume 16 Number 2 August 1992 JOSPT

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