桌球正拍拉球之生物力學分析
No Thumbnail Available
Date
2010
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
目的:探討臺灣大專甲組男子桌球選手在接上、下旋發長球時,擊出直線與斜線正拍拉球動作之運動學參數之變化,並瞭解影響擊出不同正拍拉球動作與路徑的動作特徵。方法:本研究使用Vicon Motion Capture System MX13+高速數位影像擷取攝影機(250Hz)拍攝五名臺灣大專甲組男子桌球選手在球檯左側接上旋球擊出直線、接上旋球擊出斜線、接下旋球擊出直線及接下旋球擊出斜線的正拍拉球動作,以Vicon Nexus 1.4 的軟體計算正拍拉球動作過程中的運動學參數。所有參數均透過SPSS 17.0版統計套裝軟體計算,以無母數弗里曼二因子等級變異數分析來檢定,顯著水準定為α = .05,並使用Excel計算軟體進行四種動作的事後比較。其結果發現:正拍拉球揮拍動作會因來球旋轉及揮擊路徑的不同,在各動作分期時間及時間百分比會有所差異,在接下旋球時的引拍動作時間比接上旋球長,擊斜線球比直線球的揮拍擊球動作時間短。擊球瞬間的揮拍速度與最快揮拍速度上,拉下旋球比上旋球有較快的揮拍速度。拉下旋球直線的揮拍動作過程,在引拍終點、擊球點及揮拍速度達到最快時的重心位置最低。正拍拉斜線球在擊球瞬間擊球點與身體重心前後的距離較遠,正拍拉直線球擊球點與身體重心前後距離較近。在擊球瞬間來球為上旋球時球拍角度較下旋球小。擊球點的肩部轉動角度會隨著擊球路徑而有所差異,而在肩部最大轉動角度中,正拍拉下旋球斜線的轉動角度最大,拉上旋球直線的肩部的轉動角度最小。不同的正拍拉球的揮拍過程中,上肢及下肢關節角度與角速度,會有所差異。
The purpose of this study was to investigate the kinematical variations between the movements of forehand drive in straight and diagonal line when receiving topspin and backspin services of elite table tennis male players. Five collegiate elite table tennis male players in Taiwan were served as the participants. Ten Vicon Motion Capture systems MX13+ (250 Hz) were used to collect the movements of forehand drives, and the Vicon Nexus 1.4 soft ware was used to calculate the kinematic parameters. All the variables were tested by Friedman two-way analysis of variance nonparametric statistical test which was calculated by SPSS 17.0, and the post-hoc comparison were calculated by the Excel software, the significant levels as α = .05. The results as follows: The duration time of each phase of the forehand drives were different. The duration time of backswing were significant less while receiving the backspin than receiving the topspin. The duration time of swing forward movement in diagonal line was less than in straight line. In the swing velocity at contact point and the peak velocity of swing, the drive of receiving backspin was faster than receiving topspin. The center of gravity (COG) of receiving backspin drive in straight line was the lowest among the four movements while in the end of backswing, the contact point and the fastest swing point. The relative sagittal distance between the racket and the COG at contact of forehand drive in diagonal line were more than the distance of the straight line. The racket tilt angle was less when receiving the topspin than the backspin. The shoulder axis (upper trunk) rotation of receiving backspin in diagonal line was the greatest among the four different drives, and it was the least while receiving topspin in straight line drive. There were significant differences in the upper and the lower limb joints angle and angular velocities among the four different drives.
The purpose of this study was to investigate the kinematical variations between the movements of forehand drive in straight and diagonal line when receiving topspin and backspin services of elite table tennis male players. Five collegiate elite table tennis male players in Taiwan were served as the participants. Ten Vicon Motion Capture systems MX13+ (250 Hz) were used to collect the movements of forehand drives, and the Vicon Nexus 1.4 soft ware was used to calculate the kinematic parameters. All the variables were tested by Friedman two-way analysis of variance nonparametric statistical test which was calculated by SPSS 17.0, and the post-hoc comparison were calculated by the Excel software, the significant levels as α = .05. The results as follows: The duration time of each phase of the forehand drives were different. The duration time of backswing were significant less while receiving the backspin than receiving the topspin. The duration time of swing forward movement in diagonal line was less than in straight line. In the swing velocity at contact point and the peak velocity of swing, the drive of receiving backspin was faster than receiving topspin. The center of gravity (COG) of receiving backspin drive in straight line was the lowest among the four movements while in the end of backswing, the contact point and the fastest swing point. The relative sagittal distance between the racket and the COG at contact of forehand drive in diagonal line were more than the distance of the straight line. The racket tilt angle was less when receiving the topspin than the backspin. The shoulder axis (upper trunk) rotation of receiving backspin in diagonal line was the greatest among the four different drives, and it was the least while receiving topspin in straight line drive. There were significant differences in the upper and the lower limb joints angle and angular velocities among the four different drives.
Description
Keywords
桌球, 正拍, 拉球, 上旋, 下旋, Table tennis, Forehand, Drive, Topspin, Backspin