Abstract

The purpose of this study was to examine the motor control strategies employed to control the degrees of freedom when performing a lower limb task with constraints applied at the hip, knee, and ankle. Thirty-five individuals performed vertical jumping tasks: hip flexed, no knee bend, and plantar flexed. Joint moment data from the hip, knee, and ankle were analyzed using principal component analysis (PCA). In all PCA performed, a minimum of two and maximum of six principal components (PC) were required to describe the movements. Similar reductions in dimensionality were observed in the hip flexed and no knee bend conditions (3PCs), compared to the plantar flexed condition (5PCs). A proximal to distal reduction in variability was observed for the hip flexed and no knee bend conditions but not for the plantar flexed condition. Collectively, the results suggest a reduction in the dimensionality of the movement occurs despite the constraints imposed within each condition and would suggest that dimensionality reduction and motor control strategies are a function of the task demands.

摘要

本研究的目的是检查在执行下肢任务时用于控制自由度的运动控制策略，并且在臀部、膝盖和脚踝处施加约束。35 个人执行了垂直跳跃任务：髋关节屈曲、膝关节不屈曲和足底屈曲。使用主成分分析 (PCA) 分析来自髋部、膝部和踝部的关节力矩数据。在执行的所有 PCA 中，需要最少两个和最多六个主成分 (PC) 来描述运动。与跖屈条件 (5PCs) 相比，在髋关节屈曲和无膝关节屈曲条件 (3PCs) 中观察到类似的维度减少。观察到髋关节屈曲和无膝关节屈曲条件的变异性从近端到远端减少，但对于跖屈条件则没有。总的来说，