游泳抓台式與起跑式出發之水面上與水面下運動學分析

Abstract

本研究目的為比較游泳抓台式出發與起跑式出發在水面上與水面下運動學之差異。受試者為國內優秀男子游泳選手12名，平均年齡22 ± 1.5歲，抓台式出發組身高為174 ± 3.5公分，體重為75.5 ± 4.2公斤，50公尺捷泳最佳成績為25.1 ± 0.5秒；起跑式出發組身高為177 ± 4.9公分，體重為73 ± 3公斤，50公尺捷泳最佳成績24.6 ± 0.4秒。研究中使用三部數位攝影機（60Hz）拍攝受試者水面上與水面下的動作，以Kwon3D動作分析軟體來進行資料數位化分析。研究結果中抓台式出發的出發時間為1.2秒，起跑式出發為1.1 ± 0.1秒；抓台式出發的水中滑行平均速度為2.16 ± 0.14 m/s，起跑式出發為2.23 ± 0.18 m/s；抓台式出發的海豚式振腰時間為入水後0.79 ± 0.2秒，起跑式出發為0.73 ± 0.2秒；抓台式出發與起跑式出發到12公尺所花時間為5.53 ± 0.19秒與5.45 ± 0.17秒。本研究結論為抓台式出發與起跑式出發在預備時重心位置、反應時間、動作時間及出發時間到達顯著差異，而在空中動作、進入水中動作及起身游到12m中，此兩種出發方式之間沒有差異性存在。建議游泳運動員進入水中瞬間時可透過入水前後角度的改變，與在身體重心到達最低位置前開始使用海豚式振腰踢腳動作，並根據水中動作分析後來建議選手是否適合在水中有較長的潛水時間與潛水距離。

The purpose of this study was to kinematics analyze the swimmers performing the grab and track start above and under water. Twelve male elite competitive swimmers were participated in this study. The grab start subjects data were: age 23 ± 1.9 yrs, heights 174 ± 3.5 cm, weights 75 ± 4 kg and 50m freestyle 25.1 ± 0.6 s; the track start subjects datawere: age 21 ± 1.3 yrs, heights 177 ± 4.9 cm, weights 73 ± 3 kg and 50m freestyle 24.6 ± 0.4 s. Data were collected from three video recordings (60Hz) above and under water. The video data were digitized and calculated with Kwon3D Motion Analysis System. The results of the grab start showed that: start time were 1.2s, glide velocity were 2.16 ± 0.14 m/s, dolphin kick opportunity under water were 0.79 ± 0.2 s, time to 12m were 5.53 ± 0.19 s. The results of the track start showed that: start time were 1.1 ± 0.1 s, glide velocity were 2.23 ± 0.18 m/s, dolphin kick opportunity under water were 0.73 ± 0.2 s, time to 12m were 5.45 ± 0.17 s. The conclusions of this study were: significant differences between the two techniques were the center of mass at the set position, reaction time, movement time, and start time; no significant differences between dive groups were flight time and distance, takeoff and entry velocity, entry angle above and under water, glide time and distance, and time to 12m. It was suggested that athletes should consider including changed entry angle above and under water, used dolphin kick before the center of mass at the lowest position under water, decided the glide time and distance according to underwater motion analysis.