Hore J, Watts S, Martin J
Department of Physiology, Medical Science, University of Western Ontario, London, Canada.
J Sports Sci. 1996 Aug;14(4):335-42. doi: 10.1080/02640419608727719.
The aim of this study was to determine whether, in overarm throws made by recreational ball players, the fingers undergo flexion movement before ball release and thereby contribute to the generation of ball speed. To obtain the high resolution needed to answer this question, the magnetic-field search-coil technique was used and the data were sampled at 1000 Hz. The subjects, who were either seated or were standing, threw tennis balls at different speeds at a target 3 m away. Angular positions in three dimensions were simultaneously recorded of the distal phalanx of the middle finger and hand and, in additional experiments to determine the mechanism of ball release in more detail, three middle finger phalanges and the hand. Different phases of ball release were determined by pressure-sensitive microswitches on the proximal and distal phalanges of the middle finger. Irrespective of whether the subjects were seated or were standing, for all throws at all speeds, finger flexion did not occur before ball release. That is, up until final release of the ball, the fingers only underwent extension associated with hand opening. For fast throws, at the instant of final ball release the fingers began to flex, presumably as a result of reactive forces associated with release of the ball. Thus, in overarm throws made by recreational ball players, finger flexion movement does not appear to contribute to the generation of ball speed.
本研究的目的是确定在业余球类运动员的过肩投掷动作中，手指在球出手前是否会进行屈曲运动，从而有助于球速的产生。为了获得回答这个问题所需的高分辨率数据，采用了磁场搜索线圈技术，并以1000赫兹的频率对数据进行采样。受试者要么坐着要么站着，以不同速度向3米外的目标投掷网球。同时记录中指远节指骨和手部在三维空间中的角位置，并且在另外的实验中，为了更详细地确定球出手的机制，还记录了三根中指指骨和手部的角位置。通过位于中指近节指骨和远节指骨上的压敏微动开关确定球出手的不同阶段。无论受试者是坐着还是站着，对于所有速度的所有投掷，手指在球出手前都不会发生屈曲。也就是说，直到球最终出手，手指仅随着手部张开而进行伸展。对于快速投掷，在球最终出手的瞬间，手指开始屈曲，推测这是与球出手相关的反作用力导致的。因此，在业余球类运动员的过肩投掷动作中，手指屈曲运动似乎对球速的产生没有贡献。
