男子單槓後空翻兩周轉體一周落地動作之運動學分析

Abstract

本研究是對優秀體操選手單槓比賽後空翻兩周加轉體一周落地動作進行個別的分析；受試者是來自羅馬尼亞的選手，此次實施體操動作是直體後空翻兩周加轉體360度，難度南D，選手實施動作得份是9.50。研究方式是採比賽實況攝影，利用兩部PEAK攝影機，拍攝張數為每秒60；兩部攝影機架設角度超過60度，採同步攝影；第一步攝影機離單槓中心位置17公尺，第二部攝影機離單槓中心位置14公尺。 經研究後發現受試者脫槓角度是59.2度，重心垂直速度是3.58公尺/秒，受試者空中停留時間比較短（1.12秒），同時在最大重心高度(3.59公尺)也比較低。而受試者在實施轉體動作是在脫槓後再進行轉體，整體的身姿勢及動作流暢性方面表現較優異。

In the 1997 Men’s Gymnastics Code of Points, there are changes that we should take notice. Firstly, judges are now split into groups A and, who evaluate the competitor’s starting value and deduct for errors in the routine. Secondly, the maximum amount of bonus points for men is increased from 1.0 to 1.4. Therefore, it’s very important for a gymnast to raise the starting value and reduce errors in the routine. The most important part of high bar event is dismount. The dismount has a significant influence on the trial score. The purpose of this study is to investigate the double salto backward straight with 1/1 turn, and find out the important parameters of a good dismount. A world class gymnast from Romania who was competing in the 1998 China Motor International Gymnastic Cup Championship in Taipei served the subject. The score of the trial was 9.5 point. Two Peak-Performance high speed video cameras, placed in the spectator above the floor of the competition site with 60°, were operated at 60Hz, and were genlocked to record the performance of the subject. Kinematic variables were calculated by Peak Performance Motus System, and the raw data was filtered with Butterworth algorithm. The Kinematic data was presented in Table 1. The flight time and CM horizontal flight distance were defined as 0 when releasing the bar. The total flight time was 1.12 seconds, the peak CM height was 3.59 meters, and the CM vertical velocity when releasing the bar was 3.58 m/s. The results indicated the good performance has following characteristics: (1) A longer flight time and a greater CM peak height (2) A longer peak to landing time. It is suggested that the gymnastic should increase the vertical velocity of CM during the release in order to improve the performance.