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Biomechanics and Medicine in Swimming XI

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conclusIon<br />

The present study demonstrated the importance of be<strong>in</strong>g able to generate<br />

an equation to represent a swimmer’s active drag over a range of<br />

velocities. This novel concept may provide <strong>in</strong>sight as to the suitability<br />

of the <strong>in</strong>dividual to swim specific swimm<strong>in</strong>g events, as well as, <strong>in</strong>dicate<br />

the efficiency of the swimmer’s technique. This will provide valuable <strong>in</strong>formation<br />

to coaches <strong>and</strong> swimmers regard<strong>in</strong>g the athlete’s suitability to<br />

the sport, as well as provide an evaluation of improvement <strong>in</strong> technical<br />

efficiency.<br />

reFerences<br />

Formosa, D.P., Mason B.R., Burkett B. (2009). Measur<strong>in</strong>g propulsive<br />

force with<strong>in</strong> the different phases of backstroke swimm<strong>in</strong>g. In A. J.<br />

Harrison, R. Anderson & I. Kenny (Eds.), Proceed<strong>in</strong>gs of the XXVII<br />

International Symposium on <strong>Biomechanics</strong> <strong>in</strong> Sports (pp. 98-101).Irel<strong>and</strong><br />

Kolmogorov S.V., & Duplishcheva O.A. (1992). Active Drag, Useful<br />

Mechanical Power Output <strong>and</strong> Hydrodynamic Force Coefficient <strong>in</strong><br />

Different Swimm<strong>in</strong>g Strokes at Maximum Velocity. Journal of <strong>Biomechanics</strong>,<br />

25 (3), 311-318.<br />

Mason B.R., Formosa D.P., & Rollason S. (2009a). A comparison between<br />

the values obta<strong>in</strong>ed from active drag analysis compared to forces<br />

produced <strong>in</strong> tethered swimm<strong>in</strong>g. In A. J. Harrison, R. Anderson &<br />

I. Kenny (Eds.), Proceed<strong>in</strong>gs of the XXVII International Symposium on<br />

<strong>Biomechanics</strong> <strong>in</strong> Sports (pp. 86-89).Irel<strong>and</strong><br />

Mason, B.R., Formosa, D.P., & Raleigh, V. (2009b). The use of passive<br />

drag to <strong>in</strong>terpret variations <strong>in</strong> active drag measurements. In A. J. Harrison,<br />

R. Anderson & I. Kenny (Eds.), Proceed<strong>in</strong>gs of the XXVII International<br />

Symposium on <strong>Biomechanics</strong> <strong>in</strong> Sports (pp. 452-455).Irel<strong>and</strong>.<br />

Toussa<strong>in</strong>t H.M., Roos P.E., & Kolmogorov S. (2004). The determ<strong>in</strong>ation<br />

of drag <strong>in</strong> front crawl swimm<strong>in</strong>g. Journal of <strong>Biomechanics</strong>, 37<br />

(11), 1655-1663.<br />

AcKnoWleGMents<br />

The researchers would like to thank the Australian Institute of Sport<br />

Swimm<strong>in</strong>g programme <strong>and</strong> Australian National Swim team for their<br />

participation <strong>in</strong> the study.<br />

chaPter2.<strong>Biomechanics</strong><br />

50m Race Components Times Analysis Based on a<br />

Regression Analysis Model Applied to Age-Group<br />

Swimmers<br />

Morales, e. 1 , Arellano, r. 1 , Femia, P. 1 , Mercade, J. 1 ,<br />

halj<strong>and</strong> r. 2<br />

1 University of Granada, Spa<strong>in</strong><br />

2 University of Tall<strong>in</strong>n, Tall<strong>in</strong>n, Estonia<br />

This <strong>in</strong>vestigation aimed to develop a regression model of the Race<br />

Component evolution <strong>in</strong> a large sample of regional age-group Spanish<br />

swimmers. Subjects were 280 regional swimmers selected of different<br />

clubs. The time spent start<strong>in</strong>g (ST), the time spent strok<strong>in</strong>g (STT1 -<br />

STT2), the time spent turn<strong>in</strong>g (TT) <strong>and</strong> the time spent f<strong>in</strong>ish<strong>in</strong>g (FT),<br />

were used for analysis. Inverse function approximation of the partials<br />

times by ag<strong>in</strong>g <strong>and</strong> was carried out. Furthermore, regression analysis<br />

of partials times <strong>and</strong> event time for age <strong>and</strong> genders were calculated,<br />

respectively. It seems that the times of the swimmers studied have a<br />

tendency to resemble <strong>in</strong>ternationals swimmer´s times. The estimation<br />

formula applied was different time accord<strong>in</strong>g to gender. The cross<strong>in</strong>g age<br />

<strong>in</strong> the swimm<strong>in</strong>g partials times were about 12-14 years old.<br />

Key words: performance development, competition analysis, technique<br />

test<strong>in</strong>g<br />

IntroductIon<br />

The dynamic process of tra<strong>in</strong><strong>in</strong>g needs as much <strong>in</strong>formation as possible<br />

from competitive performance, which, together with <strong>in</strong>formation from<br />

tra<strong>in</strong><strong>in</strong>g <strong>and</strong> test<strong>in</strong>g, will help to the coach to monitor the tra<strong>in</strong><strong>in</strong>g program.<br />

Race components (RC) data must be considered when analys<strong>in</strong>g<br />

swimm<strong>in</strong>g performances dur<strong>in</strong>g <strong>in</strong>ternational swimm<strong>in</strong>g competitions<br />

(see www.swim.ee). To improve the swimmer test<strong>in</strong>g efficiency, this<br />

analysis has also to <strong>in</strong>clude the results of swimm<strong>in</strong>g tests made dur<strong>in</strong>g a<br />

tra<strong>in</strong><strong>in</strong>g season or several tra<strong>in</strong><strong>in</strong>g seasons.<br />

The RC is composed of the start<strong>in</strong>g time (ST), strok<strong>in</strong>g (STT),<br />

turn<strong>in</strong>g (TT) <strong>and</strong> f<strong>in</strong>ish<strong>in</strong>g (FT) (Pai, Hay, & Wilson, 1984). Swimm<strong>in</strong>g<br />

tra<strong>in</strong><strong>in</strong>g has to be oriented to improve all rac<strong>in</strong>g components, but<br />

the lack of a specific model makes it difficult to know which are the<br />

strongest <strong>and</strong> weakest race components of any <strong>in</strong>dividual. The coach<br />

must tra<strong>in</strong> the swimmer accord<strong>in</strong>g to swimm<strong>in</strong>g time <strong>and</strong> age. The<br />

50m freestyle performances should improve with age <strong>in</strong> each period of<br />

growth, <strong>in</strong> parallel with the RC.<br />

Some studies have been published where regression equations were<br />

applied <strong>in</strong> the analysis of RC obta<strong>in</strong>ed from different competitions (Absaliamov<br />

& Timakovoy, 1990; Arellano et al., 1996; Nomura, 2006). The<br />

study aim was to develop a regression model of the RC evolution <strong>in</strong> a<br />

large sample of regional age-group Spanish swimmers.<br />

Methods<br />

The sample was composed of 180 regional swimmers (162 males <strong>and</strong><br />

118 females). The age of these subjects ranged from 9 to 22 years.<br />

The procedures that have been used to record the times obta<strong>in</strong>ed<br />

by swimmers dur<strong>in</strong>g the performance test of 50 m freestyle were: a)<br />

references were put on the swimm<strong>in</strong>g pool at the distances selected (5,<br />

10, 15 <strong>and</strong> 20 m) to know when the head crossed this l<strong>in</strong>e; b) the 50m<br />

trials were recorded by five video cameras connected to a m<strong>in</strong>i DV video<br />

recorder through a video-timer <strong>and</strong> video selector; c) the images from<br />

the first two video cameras were mixed to see the over- <strong>and</strong> under- water<br />

phases of the start <strong>in</strong> the same frame (until 5m); d) third <strong>and</strong> fourth<br />

cameras were used to measure the 10 <strong>and</strong> 15 m time; the fifth camera<br />

was placed at the end of the swimm<strong>in</strong>g pool for video record<strong>in</strong>g the<br />

turn<strong>in</strong>g phase (20 <strong>and</strong> 25 m) <strong>and</strong>; e) all the images from the cameras<br />

127

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