Biomechanics and Medicine in Swimming XI

dIscussIon
Task 1: The difference between normal and pre-test 1 on timing and displacement
indicated that the swimmer could change the movement immediately
while listening to the sound (see Figure 3). After Task 1, there was
no significant difference between pre-test 1 and post-test 1. Although DE
values in pre 1 and post 1 both were lower than the normal, our expectation
was that DE value would decline more in post-test 1 than pre-test 1 because
variable sound scales (i.e. 75 % and 50 % sound) could train relative hearing
(Miyazaki, 1993) and thus affect the vertical displacement, approximating
the target movement. Task 1 would indicate that changing sound scale
randomly (meaning changing height of dolphin kick displacement) has no
effect for dolphin kick movement.
Task 2: The results of TE on post2, post3, post4 and post5 indicated that the
subjects retained the approximate dolphin kick timing to the target without
the sound (see Figure 4). The auditory model has been a quite effective
aid for timing patterns (Charles et al., 2001). If a coach wishes to change a
swimmer’s movement, a target sound could have an effect on his/her timing
or help to create a constant tempo during training. The result of DE, in
spite of the displacement of the target swimmer movement expressed on a
sound scale, there was no difference after Task 2. There were, however, significant
differences between three trials (see Figure 4). It would appear that
the subject’s concentration on sound retention in Task 2 did not influence
his/her performance in post2, but a non-auditory environment made the
swimmer focus on receiving kinesthetic feedback. They could later reproduce
the movement facilitated by the target sound.
This study indicates that an auditory model can be useful to set a swimming
pace or to immediately coordinate timing. The dolphin kick, however,
is but one parameter of movement. In the real world of training, the coordination
and timing of strokes is based upon several parameters (e.g. kick and
arm coordination, arm finish and breath, etc.). A study of the use of auditory
models in swimming should focus on parameters that could be coordinated.
In this study, displacement of the toe of the model swimmer was expressed
on a sound scale. But the swimmer’s displacement error decline from
the target appeared a few minute later without the sound (see DE graph
on Figure 4). It seems that retention and reproduction of movement were
sequential steps according to the motor learning cognitive process (Schmidt,
1991). Listening to the sound scale change and feeling his/her toe displacement
from kinesthetic sensation at the same time, for detection of error
would be very hard for the swimmer underwater.
conclusIon
The target sound was effective for skilled swimmers learning movement timing.
Learning displacement was difficult utilizing sound but would be more
effective with the learning steps of retention and reproduction in the correct
sequence.
reFerences
Charles H.S., Gabriele W., Jin-hoon P. & Briana, G. (2001). Effects of an
auditory model on the learning of relative and absolute timing. Journal of
Motor Behavior, 33(2), 127-138.
Fusco, N. & Crétual, A. (2008). Instantaneous treadmill speed determination
using subject’s kinematic data. Gait & Posture, 28(4), 663-667.
Lin, W. & Melanie A.H. (2005). Influence of auditory modelling on learning
a swimming skill. Perceptual and Motor Skills, 100, 640-648.
Seifert, L., David, L., Ragis, T. & Chollet, D.. (2006). Auditory concurrent
feedback benefits on the circle performed in gymnastics. Journal of Sports
Sciences, February, 24(2), 149-156.
Miyazaki, K. (1993). Absolute pitch as an inability: Identification of musical
intervals in a tonal context. Music Perception, 11, 55-72.
Schmidt R.A. (1991). Motor learning and performance, Champaign, IL: Human
Kinetics.
Yamamoto, M. (2007). Support of motor learning by auditory feedback. Unpublished
master’s thesis, University of Electro Communications, Chofu
City, Tokyo, Japan.
chaPter5.education,adviceandBiofeedBack
Tendencies in Natural Selection of High Level Young
Swimmers
timakovat.s., Klyuchnikova M.V.
All-Russian Scientific Research Institute of Physical Culture and Sport,
Moscow, Russia
High performance levels in modern sport require great physical and
psychological effort from young athletes. Some specialists conduct the
early orientation for children with unusual abilities and gifted young
ones. This problem has difficulties not only in search of such criteria
but also in some social and moral aspects. The aim of the study was to
find out facts of change in young swimming leaders, and to discover the
reasons of this replacement. The retrospective investigation was done,
using data of young swimmers demonstrating high age group performance
levels. The analyses have shown a clear tendency to change selection
criteria according to age group. Also the differences in biological
maturity between swimmers of both sexes were revealed. The greatest
variance in age development typology was observed in the age groups
of 13-14 years.
Key words: age group, biological age, high level, natural selection,
generation.
IntroductIon
Over the last 30 years sport has often been criticized for being both
institutionalised and for the premature specialisation of children and
youth sports. The lower age threshold of children’s entry into “organised”
sport has dropped from 6-8 to 4-6 years. So an early introduction to
training and competition occurs more frequently and in a similar format
to the adult paradigm (Schmidt 2001).
According to expert opinion (Brettschneider, 2001, Schmidt 2001)
this contributes to the development of early mental fatigue and children’s
exit from sport. Some researchers feel the need to have different
development models of activity for children, such as: a holistic focus and
special programs for future champions (Brettschneider 2001). However,
when adopting this approach we must employ serious scientific estimation
methods in order to assess the potential of each child and teenager.
Obviously, early talent identification and an appropriate orientation towards
elite sport will avoid a misguided intensification for the majority
of youth.
Our research confirms the presence of phenotype features of swimmers
with different levels of achievement. However, we believe in the
necessity of establishing prognostic criteria for the talent search within
sports. In our opinion the main task of preparing young athletes consists
of the clear and suitable matching of the proposed training loads to the
possibilities of the developing young organism. This primarily concerns
problems around the optimization of sports preparation (Bulgakova &
Tchebotareva 1999, Klyuchnikova 2000, Timakova 1985).
In this article the research material is presented to display the necessity
of making allowances for features of biological development.
This permits qualitative management of the selection (talent hunt) and
preparation of young swimmers.
Methods
Retrospective analysis of the best swimmers’ research data in different
age groups was done. In total 210 girls and 216 boys covering the age
ranges of 12 to 19 years were surveyed. The data were analysed according
to their placement in different generations of the country’s national
swimming teams. One generation of swimmers is from the decade of the
1990s; the other from the first decade of the new century.
Programs of testing included: 1) Anthropometry and the definition
of biological age; 2) Swimmers’ bio-energetic parameters and functional
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