Hiley Michael J, Yeadon Maurice R
School of Sport, Exercise and Health Sciences, Loughborough University, UK.
School of Sport, Exercise and Health Sciences, Loughborough University, UK.
Hum Mov Sci. 2016 Oct;49:95-103. doi: 10.1016/j.humov.2016.06.011. Epub 2016 Jun 28.
When performing a giant circle on high bar a gymnast flexes at the hips in the lower part of the circle, increasing the kinetic energy, and extends in the upper part of the circle, decreasing the kinetic energy. In order to perform a sequence of giant circles at even tempo, any variation in angular velocity at the end of the flexion phase needs to be reduced by the end of the extension phase. The aim of this study was to determine the nature and contribution of such adjustments. A computer simulation model of a gymnast performing giant circles on high bar was used to investigate strategies of (a) fixed timing of the extension phase (feedforward control) and (b) stretched timing in order to extend at the same point of the giant circle (feedforward with additional feedback control). For three elite gymnasts fixed timing reduced the angular velocity variation on average by 36% whereas stretched timing reduced the variation by 63%. The mean reduction for the actual gymnast techniques was 61%. It was concluded that both feedforward and feedback control strategies are used by gymnasts for controlling such movements.
在高低杠上做大回环时，体操运动员在回环的下半部分屈髋，增加动能，而在回环的上半部分伸展，减少动能。为了以均匀的节奏完成一系列大回环动作，在屈髋阶段结束时角速度的任何变化都需要在伸展阶段结束时减小。本研究的目的是确定这种调整的性质和作用。使用一个在高低杠上做动作的体操运动员的计算机模拟模型，研究（a）伸展阶段固定时间（前馈控制）和（b）延长时间以便在大回环的同一点伸展（带有额外反馈控制的前馈）的策略。对于三名优秀体操运动员，固定时间平均将角速度变化减少了36%，而延长时间则将变化减少了63%。实际体操运动员技术的平均减少率为61%。得出的结论是，体操运动员使用前馈和反馈控制策略来控制此类动作。
