Publication:

網球截擊之三維運動與動量分析

中文摘要

本研究之目的在於（一）建立重擊式與點擊式截擊在不同擊球側時，上肢各關節與軀幹之運動學資料；（二）比較重擊式與點擊式截擊動作及不同擊球側之差異；（三）透過肢體動量傳遞的參數以及球速的差異，探討兩種截擊動作的效果。本研究以六位男性的全能型網球選手為實驗對象（平均年齡26.5□9.4歲、身高173.3□3.8公分和體重67.3□11.0公斤），所有實驗參與者慣用手為右手。利用HiRES三度空間運動分析系統，以六台攝影機收集各實驗參與者截擊時的肢體運動軌跡影像資料。量化分析優秀的網球選手在不同截擊狀態下的軀幹和上肢在網球重截擊與點截擊動作之運動學及動量參數，並以t檢定（t-test）方法比較截擊方式及不同擊球側角運動的差異。本研究所得結果如下：在比較不同擊球側之角運動範圍，兩種截擊動作都沒有顯著的差異。比較不同擊球動作之角運動範圍，以前臂在反拍加速期的旋前/旋後運動具有顯著差異（p<.05，ES=1.54）。兩種截擊的線動量都是以前臂的線動量最高，即截擊動作主要動量是由前臂而來，重截擊時軀幹及肩關節會產生較大運動範圍，如此，可產生較多動能。而腕關節的運動較少，其主要弁酮偕□驧藤鷏`穩定並將球之動能反彈回去。研究結果將可提供網球教練與選手在截擊訓練及成果評估。同時，亦有助於臨床醫師及治療師在網球之運動傷害的診斷及臨床治療。

ABSTRACT

The purpose of this study was to 1) quantify the kinematics and linear and angular momentum of upper extremity in tennis volley; 2) investigate the effects of the volley technique and hand drive type, forehand and backhand, on biomechanical behavior; and 3) understand how segment momentum transfer affects the ball velocity at impact. Six male tennis players (mean age 26.5□9.4 yrs; height 173.3□3.8 cm; weight 67.3□11.0 kg) with right dominate side were recruited in this study. The six-camera HiRES Expert Vision motion system (Motion analysis Corp., Santa Rosa, CA, USA) was used to collect the motion of the upper extremity and trunk during tennis volley using two volley techniques, punch and drop, as well as forehand drive and backhand drive at sampling rate of 240 Hz. Ten trials were collected for each technique and drive type for each subject. Each trial lasted for 8 seconds with 3-minute rest between trials. A developed biomechanical model of upper extremity was used to compute the three-dimensional (3D) joint motion and momentum of the trunk and upper extremity. Student t-test was used to compare the differences between volley techniques and drive types. The results showed that the range of motion (ROM) in forehand and backhand was no significant different In the acceleration phase, this study found that the ROM of forearm pronation/supination in backhand were larger than forehand (p<.05, ES=1.54). The ROM and velocity in the trunk and shoulder in punch volley may indicate that it requires greater rotatory momentum to bounce back the ball compared to drop volley. In the contrast, greater forearm pronation and wrist joint motion in drop volley demonstrated that the forearm and wrist played an important role in the ball control. These results are similar to previous findings in backhand volley. Understanding of the 3D biomechanical behavior of upper extremity during different types of tennis volley could allow tennis players and coaches to improve the performance of tennis technique and prevent injury. It is also helpful for the physicians and therapists in diagnosis of sports injury and clinical treatment.