The moment formed by COP with the whole body center of mass would then be analyzed to investigate the kinematic characteristics of the body.

• 此外，在二维运动学资料中，上旋发球较平击发球于加速期时生成较多的膝关节弯曲，同时在骨盆生成较多的后倾，如此可帮助增加发球时之动量生成及传递。