# TECHNIQUE AND TRAINING OF THE SHOT PUT AND DISCUS

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```					TECHNIQUE AND TRAINING OF THE
SHOT PUT AND DISCUS THROW
By Altmeyer, L. - Olympic Training Centre of Saarland, State Coach of the Throwing
Events; Bartonietz, K. - Olympic Training Centre of Rhineland-Palatinate,
Biomechanical Training Adviser for the German Track & Field Association; Krieger,
D. - Palatinate State Director for Teaching and Coaching

4th Annual Coaches Clinic, February, 12 & 13, 1993, takes a look at various
biomechanical issues in the Discus and Shot Put throws and offers some advice for
technique development and training.

Mu t fr o
1 Biomechanical Knowledge - a“ s” o C aching

All movements of men and animals are determined by the laws of mechanics. It is the first
task of science (but only the first) to understand movements of athletes; therefore it is an
indispensable base for coaching.

In the throwing events the factors influencing the performance are classified into:

 the physical laws of the flight phases of the implement and;

 the biomechanical laws of the movement of the ss m ‘ rw r n i l n’
e h           e
yt t o e a d mp me t
before release.

1.1 Movement of the implement after release (external ballistics)

The most important factor for a long throw is the velocity of release. It is the only one factor
o e x e y h tl e co ;h te (e h o rl s ,e a e n l ) a
mi                e s i                    g
t b ma i z db teah t’a t n teoh rh i t fe a e rl s a g s c n     e          e         e
only have optimal levels. Notwithstanding the square influence of release velocity (see eq.
1), the linking with other parameters causes a linear relation between release velocity and
flight distance of the implement.

R = range (m)
V0 = velocity of release (m/s)
α = direction of V0 (degree)
0
h0 = height of release (m)
g = velocity of the Earth (9.81 m/s2)

The optimal angle of release for a shot putter is 42 degrees, for discus throwers 35-37
degrees at an angle of attack of 10-15 degrees less (see figure 1).
This way the implement gets a lift in the middle part of the flight phase. Changes of the
angle of attack of ± 2 degrees can be ignored.

The wind has a major influence on the flight phase in discus throwing. Optimal conditions
exist when there is a headwind from the right side. A headwind from the left side requires
to put down the edge of the implement to the right side. The interaction of wind speed and
direction is very complicated and must be taken into consideration in training and
competition.

After release the discus rotates with 5-8 rps. Figure 2 shows the differences between a
spinning and no-spinning implement. It emphasizes the importance of the delivery
movement.

Fig. 2: Trajectories and orientation of spinning and no-spinning discus (investigation
of SOONG 1982)

The wobble can also occur if the contact with the implement is negatively influenced (rain,
perspiration).

A change in the release height corresponds approximately to the change in the distance
thrown. Therefore the selection of a reverse or a non-reverse delivery depends on the
physical abilities of the athlete.

v me t fh yt athlete and implement’
e
1.2 Mo e n o tess m ‘                   before release (internal ballistics).

The impulse of the competition implement is the result of accelerations and decelerations
of different parts of the throwers body. The athlete must transfer a great deal of kinetic
energy in a short time interval on the implement. In other words - he must achieve a great
power level:

Energy
Power =              kW (previous horse power)
Time
In effect, the athlete must achieve a larger quantity of energy in a shorter time interval,
s
because the velocity of the thrower’body increases while the time available decreases.
The coach cannot necessarily expect a carry-over value of increased power value to
competitive performance.

Therefore, the coach should always strive for an increase of the physical power under
specific conditions (speed, mass of implement, path) as a prerequisite for better
performances.

The following figure shows the power level, the forces of acceleration and the velocity level
at the beginning of the delivery of an excellent shot put and discus throw.

Fig. 3: Force-time relations (top), force-path relations (below) and main parameters
fh mp me te
o tei l n’mo e n  s v me t

The most important thing is to exert more energy on the implement in a shorter time.
s e il h p h okof
ay         u
The efficiency of the legs is the basis for the throwing events, e p c l te‘ s w r’
the right leg (acceleration of the centre of gravity) and the brace work of the left
(deceleration of he centre of gravity) . Figure 4 shows the ground reaction forces at
excellent throws of elite athletes. They must be shining examples for young athletes:

Figure 4: Ground reaction forces vs. time in a shot put and discus throw.

The power demands for the bracing action of the left leg in shot put and discus throwing
are almost 3 times the level of the right leg. Therefore the efficiency of the right leg is at
first a problem of coordination while the left leg requires more strength. But in reality the
ai si ) n bi (t n t)a tee
o     l s        lt r
thrower makes no difference between coordin t n(kl a da iy s e gh, s h r’                     s
a unity between them. We must take it into consideration in the training process:

TECHNIQUE WITHOUT POWER - NO POWER WITHOUT TECHNIQUE

Without effective leg work - no high performance. The necessary internal working
conditions for the main muscle groups (e.g. the level of pre-tension) can also be judged
from the external picture of motion:

ra “
Fig. 5: Body position at the greatest tension and path of the right hip joint (intev lplanting
xma t s n)
e o
the right foot - ma i l n i ”in throws of Ulf Timmermann (BARTONIETZ 1990)

The following suggestions are based on very personal experience. This is why we
recommend:

1. General Exercises to establish a sufficient level of agility

 Equilibrium, balance, coordination, orientation, rhythm

 For this purpose other kinds of sports may be useful

o skiing, skating, dancing, gymnastics, trampoline, games, etc.
2. Special Exercises

 Balance: various kinds of rotation on the ball, slowly and controlled

 Turns: on the spot, forward turns with/without acceleration, turns with finish in
various positions

 Throws: with different implements (balls, shoes, etc.)

 Discus: get used to the implement. Experience how the implement reacts on
different movements (swings, rolling, spin)

3. 360 degree Turns With Delivery (with other implements)

 Stand facing the front.

 Start turn with left foot forward.

 Put special emphasis on the rhythm (clap, shout)

 Finish without reverse in double-leg supported position (the right leg just
helps balancing)

 Use different implements. Mind the danger of accidents.

 Coach and athlete control final position!

4. 360 Degree Turns With Delivery (with discus)

 Same execution as the previous step.

 Experience proved that this approach can be done well. For example, the
heavy fault of grounding the right heel in the power position occurs far less
than when beginning to teach the discus from the standing throw.

5. 450 Degree Turns With Delivery

 Attention is paid now especially to the start and the balance position

 The transfer of the bodyweight onto the left bent leg is important.

6. Advance to Full Turns (540 degrees)

As soon as the basic technique is established all other known drills should be used to
, n o e h tl e “l ”
t         e     a
improve the skill level, for motivation a dt l teah ts p y with their movement.

Rg t” n Wrn s o T c nq
2 Observing and Recognizing “ ihs a d“ o g ” f e h iue Development.

Movement observation - by the coach, by a training partner, or by self observation is the
most common and most important control factor in technique training. The skill level is
maintained and faults and their causes can be analyzed to decide the methodical steps to
follow. This sounds simple. However, a number of conditions have to be fulfilled if real
success to be achieved.

2.1 Concept of the technique

The coach and the athlete must possess an exact concept of the event. These concepts
are not only descriptive but must also take into consideration functional aspects such as:

 biomechanical: e.g. interaction of body parts;

 reactive functions: slight t d l atrh gd ;
a e e      i
s d ’ f te le

 steering functions: concentration on a fast transfer from the glide to the delivery.

h n we e fh e u n e o te e h i e n h k y e u n e ”te h t
d                                  q
T ek o l g o tes q e c s fh tc n u a dte“e s q e c s,h ry m,                          h
the speed and the acoustic of it is as important as having seen many illustrations, athletes
in action, having gained own practical experiences and held many discussions with other
coaches and athletes.

Knowing the most common faults, the degree of difficulty of the technique and the ability to
decide if a deviation of the ideal pattern is to be handled as a fault or a matter of personal
style are other requirements of a good concept.

 Good coaches and athletes constantly try to perfect their concept.

2.2 Movement Observation and Analysis

 The coach and the athlete have to be trained to observe movements.

Many coaches just stand there watching the attempts without any strategy. They get a
general impression of the quality of the attempt. What is striking is a matter of chance.

The short duration of a movement pattern restricts the coach to only a limited number of
observation criteria or an impression of the complete action. The athlete, facing a double
task (controlling the movements and self-observation), can usually establish even less.

An observation is seldom objective, different observers would come to different
conclusions about the same attempt. The coach and the athlete are therefore frequently
surprised to discover in a video study what they had not recognized or what occurred
entirely differently. The human eye can be far too often misleading. That is why the coach
has to use a strategy of observation.

 Decide what you want to observe!

f o o ’ n w h h f lh rei o ac y u s t upi d h t o
t          c
Iy ud n k o w i o a teci r y uw t , o mu t’ es rr e ta y u
l       ta            h       nb     s
a ’ ok yt tay
t      e cl
barely succeed in promoting the skill level. Youc n w r ss mai l.

 Decide if you want to use video equipment or not!

 Reduce the number of criteria to observe (2 –4, y ud n u ev e !
f      t    d
)i o o ’ s i o
A coach is only able to observe 1-4 criteria. By that number the risk of seeing something
not correctly or precisely is low.

 Decide where you can observe your criteria best from!

 If necessary, change your point-of-view to observe the same criterion (from the side
or the back)!

 Decide how many attempts you check!

t et n u e o at t y u r b o e i , a f l h s cur y
h      a                e                   e      d f at
Wi ac r i n mb r f t mps o aea l t d c e i “ u ” a o c r db                    e
chance, occasionally or regularly. Different consequences will have to follow.

t i s r h” rw o g!
eo    i
Decide if a cri r ni“g to “ rn ”

If the movement concerning the criterion observed has been executed correctly, give
feedback but only after a couple of attempts. If not, analyze the fault.

2.3 Fault analysis

The coach and the athlete must be capable of analyzing faults. Do faults involve
conditional, motor-learning or psychological factors?

For a better understanding look at the following simple model of motor-learning.
Faults can be caused by:

 Wrong demonstration of the task.

 The demonstration cannot be observed well enough.

 It might have been explained in a too difficult way (too much information, phrases
l e a ’ n es d.
e      t
the ath t c n u d rtn ) a

 The athlete has been disturbed by something (mental, surrounding).

 The concept of the movement is not exact or not complete. The athlete is afraid of
something.

 The conditional requirements for a correct execution have not been given.

 Bad facilities or implements, weather-conditions.

fe c o ’
u
These factors of inl n ed n occur separately but in a complicated interaction (e.g.
t
skills and abilities)

2.4 Correction of faults

The coach has proven methodical knowledge and experience and understands how to
teach and evaluate skills.

 D f ete“ i a l. h way, you are able to eliminate also those mistakes
n         n
ei h ma -fu ”T i   t    s
which are caused by the main-fault.

For the most common faults you get plenty of hints in various books. Try them or find own
methodical ways to solve the problem.

If the athlete does not succeed in eliminating the error, stop training because the fault
would be automated, the wrong skill would be stored in the motor memory.

me s r g te uality of the movement
n
2.5 “ a ui ”h q

Usually you measure the performance of a throw in meters and centimeters/feet and
c e ,h tl e ef ma c f p e n e o d , n e/ s t n t n
e s       o
in h s teah t’p r r n eo s e di s c n s a dh r is e ghi         h r
kilogrammes/pounds. This is why you need precise information on the actual level of
performance to plan the subsequent training cycles. All these pieces of information are
documented over the years.

Why should you not measure and document the quality of the movement?

 You can demonstrate how the motor skills of the athlete develop.

 You can find out differences after different training cycles or various kind of training.

 You can see which faults occur by chance, occasionally or regularly.
2.6 Analysis Sheets

i h es r rcc lt l for
s                   i os
Analys s e t aepa ta “ o ” observing and analyzing movements and
measuring the quality of a movement sequence (TIDOW, McGILL, KRIEGER).

Most analysis sheets published contain a list of main movement criteria relevant to a basic
model of the technique. The criteria are illustrated by either stick figures or drawings. The
sequences selected are described so that every user who knows the target technique can
reliably decide, if a partial movement was performed correctly. For exact measurement of
the quality of the movement analysis sheets have to fulfill the requirements of statistical
tests: validity, objectivity and reliability.

Validity is gained by acceptance of the criteria given by experts in the event.

Objectivity means that every user of the analysis sheet comes to the same conclusion.

Reliability is proven e.g. if you get the same result after recreating the checking of the
same attempt.

With these analysis sheets coaches have tools available that help to evaluate the quality of
movements considerably.

2.7 Operating the analysis sheet

Two methods are suitable to operate the sheet during technique training sessions in order
to measure the actual skill level:

1. Video:

 The movement is recorded about 10 times (random choice from about 30
attempts) . The recorded studies are evaluated exactly according to the analysis
sheet.

 The advantage of this procedure is that it uses technical possibilities for
exactness (slow motion, stills, repeated, observation) and can be recommended.

2. Observation with the naked eye:

 The coach limits her/himself to 2 - 4 criteria, evaluating these in about five
attempts that follow each other, before entering the result on the analysis sheet.
The next set of criteria will follow suit.

 The complete picture of the quality of the movement in this method is not as
precisely established as in the previously suggested approach. However it is still
more reliable than observations based on the total action alone, particularly
when the observations are limited to the previously identified faults in movement
elements.

Filling the analysis sheet the coach enters a plus (+) in the corresponding column of
attempts when the criterion has been achieved or a minus (-) if the performance was
faulty. If a fault occurs frequently or continually after 5 to 10 attempts, the identified fault
must be eliminated by the use of appropriate methodical measures. This will lead the
athlete closer to the target technique in the following training process

2.8 A sample analysis sheet

All analysis sheets published contain more than 30 criteria.

For an exact analysis by usage of video systems all of them are applicable. You choose
the one you can handle best.

For a handy application - especially for training at schools and clubs - KRIEGER tried to
rei f i n l i h e “h t u” yt
ta        s       ys
reduce the number of ci r o h a a s s e tS o P tb i m-analysis:     e

 Degree of difficulty of an criterion

o The problem had been to find out which of the criteria are performed by 20 to
0     fh ho es e t . h ho esw r 3
e
8 % o tetrw r ts d T etrw r’ ee1 - 14-years-old students
who had learned and trained the Shot Put. If more than 20 % of the throwers
failed with a particular item, it was regarded too difficult. If more than 80 % of
the students performed the criterion correctly, it was regarded too easy, i.e.
the chance of failure is small.

 Degree of discrimination

o Had the criterion been performed well only by good throwers or had there not
been any difference?

o Only criteria with a correlation of more than .30 had been selected.

By this approach a loss of information has to be taken into consideration, because
observation is concentrated on the main criteria which influence the performance most.

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