Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan.
J Sports Sci. 2009 Oct;27(12):1233-40. doi: 10.1080/02640410903233222.
In tennis, a "split-step" is a small vertical jump or hop that is commonly used as a preparatory motion for a lateral step when receiving the ball. The purposes of the present study were (1) to determine whether a split-step increases the velocity of the subsequent lateral step, and (2) to investigate when the landing should occur in order to obtain the maximum benefit from a split-step. Ten male collegiate tennis players performed a choice reaction step-and-reach task with and without a split-step. The participants could reach the target earlier by taking a split-step (split: 764 +/- 106 ms, no-split: 868 +/- 63, P < 0.001). A risk-benefit relationship of a split-step depended on the timing of the landing. If the interval between the activation of the direction signal and the landing was shorter than mean minus standard deviation of the participant's response time, participants sometimes achieved very quick step to the target but could not reach the target in 7.8% of the trials. On the contrary, if the interval between the activation of the direction signal and the landing was within the mean plus-minus standard deviation of the participant's response time, participants achieved quick and reliable (percentage of error: 0.8%) step.
在网球中，“分腿垫步”是一种常见的预备动作，用于在接发球时进行侧向跨步。本研究的目的是：（1）确定分腿垫步是否会增加后续侧向跨步的速度；（2）研究在何种情况下落地可以从分腿垫步中获得最大收益。10 名男性大学生网球运动员在有和没有分腿垫步的情况下进行了选择反应步测任务。通过分腿垫步，参与者可以更早地到达目标（分腿：764 +/- 106 ms，不分腿：868 +/- 63，P < 0.001）。分腿垫步的风险收益关系取决于落地的时机。如果方向信号的激活和落地之间的间隔短于参与者反应时间的平均值减去标准差，那么参与者有时可以非常快速地向目标迈进，但在 7.8%的试验中无法到达目标。相反，如果方向信号的激活和落地之间的间隔在参与者反应时间的平均值加减标准差范围内，那么参与者可以实现快速且可靠的（误差百分比：0.8%）跨步。
