跆拳道兩種預備站姿跳後踢之生物力學分析

Abstract

跆拳道（Taekwondo）是我國亞奧運重點奪金項目，跳後踢是跆拳道比賽中經常被應用於反制旋踢的主要踢法之一。本研究旨在探討不同預備姿勢下進行不同高度跳後踢動作的動作特徵與差異，及其生物力學參數對踢擊表現的影響，以做為跳後踢動作訓練及指導之參考依據。本研究以10名跆拳道優秀選手為受試對象（年齡：20.4±1.5歲；身高：177.9±2.4公分；體重：64.7±2.6公斤）。利用兩台AMTI測力板 (1000Hz)、十部Motion Real Time高速攝影機（200Hz）和Bio-pac MP35壓力感測系統，同步蒐集受試者在跳後踢動作過程中的運動學和動力學資料。部份角運動學及動力學參數需透過Matlab 7.01自行編寫程式來計算，統計方法主要是以無母數統計檢定（Nonparametric tests）來考驗不同預備站姿與不同踢擊高度生物力學參數之差異，並以皮爾森積差相關檢定各運動學和動力學參數對踢擊表現之影響。本研究主要發現如下： 一、 動作速度方面：「預蹲中端」、「跳動中端」和「跳動上端」明顯快於「預蹲上端」，而「預蹲中端」和「跳動中端」之間則無明顯差異。 二、 踢擊力量方面：「預蹲中端」、「跳動中端」和「跳動上端」明顯大於「預蹲上端」，而「預蹲中端」與「跳動中端」之間則無明顯差異。 三、 軀幹旋轉角速度方面：「跳動中端」和「跳動上端」之肩軸角速度峰值明顯大於「預蹲上端」，而「跳動中端」亦明顯大於「預蹲中端」 四、 地面反作用力方面：「跳動中端」、「跳動上端」之攻擊腳在前後、垂直方向的地面反作用力峰值及衝量均分別明顯大於「預蹲中端」、「預蹲上端」。

Taekwondo is a national sport in Taiwan which can win medals in Asian Games and Olympic Games. Jumping-back kick is used in competition to counterattack round-kick. The purpose of this study was to describe the movement characteristics of jumping-back kick at different height from two preparatory standing postures (jump and squat) in order to provide information for teaching and training of jumping-back kick. The participants included 10 elite Taekwondo athletes whose mean age, height, and weight were 19.7±0.8 yrs, 178.6±3.5 cm, and 66.0±6.4 kg respectively. The kinematics and kinetics data of jumping-back kick were collected simultaneously by two AMTI force plate (1000Hz), ten motion system cameras (200Hz), and Bio-Pac MP35 pressure measuring system. The angular kinematics and kinetics data were calculated by program written in Matlab 7.01 software. Nonparametric statistic test was used to test the difference of parameters among two preparatory standing postures and two kicking heights （jump preparatory standing posture-middle height kicking [JK1], jump preparatory standing posture -top height kicking [JK2], squat preparatory standing posture- middle height kicking [SK1], squat preparatory standing posture-top height kicking [SK2]）. Pearson product-moment correlation was conducted to determine the relations of each parameter of kinematics and kinetics to kicking performance. The results were showed as below: 1. JK2 had faster movement speed than did SK2. There was no difference between JK1 SK1 and regarding movement speed. 2. JK2 had greater impulse force than did SK2. There was no difference between JK1 and SK1 in impulse force. 3. Regarding the angular velocity of trunk, the maximum angular velocities of shoulder axes at JK2 was greater than that at SK2. Besides, the maximum angular velocity of shoulder axis at JK1 was greater than that at SK1. 4. JK1’s and JK2’s offensive foot have the greater peak vertical ground reaction force (GRF) and peak anterior-posterior force and impulse than were SK1’s and SK2’s offensive foot. Conclusion: In terms of the results, jump preparatory standing posture will facilitate the better kicking performance when perform jumping-back kick at top height target. Therefore, jump preparatory standing posture is recommended for taekwondo athletes and coaches in skills training for kicking at top height targets.