Université de Bourgogne, Dijon, Campus Universitaire, UFR STAPS, Dijon, France.
Exp Brain Res. 2010 May;203(1):147-58. doi: 10.1007/s00221-010-2219-1. Epub 2010 Mar 26.
The aim of this study was to determine whether the timing of the muscular synergies was influenced by the reduction of the base of support when we initiate a whole body reaching movement. To answer this question, we performed a principal component analysis on electromyographic activities of 24 muscles recorded on the leg, the trunk, and the arm. Our results demonstrated that during the initiation of the whole body pointing movement, only three principal components accounted for at least 95% of the variance for the overall muscular data, both when the equilibrium constraints were normal and when the base of support was reduced. These principal components were strongly correlated despite the fact that the center of mass forward displacement and the center of pressure backward displacements significantly decreased when the base of support was reduced. It suggests that the central nervous system did not change the overall timing of the muscular synergies when new equilibrium constraints were introduced in the task but was rather able to tune their amplitude as evidenced by the modification of the center of mass and center of pressure displacements.
本研究旨在确定在进行全身伸展运动时，支撑基础的减小是否会影响肌肉协同作用的时间。为了回答这个问题，我们对记录在腿部、躯干和手臂上的 24 块肌肉的肌电图活动进行了主成分分析。我们的结果表明，在进行全身指向运动的初始阶段，无论平衡约束是正常的还是支撑基础减小的情况下，只有三个主成分至少占整个肌肉数据方差的 95%。尽管支撑基础减小会导致质心向前位移和压力中心向后位移显著减小，但这些主成分仍然高度相关。这表明，中枢神经系统在任务中引入新的平衡约束时，并没有改变肌肉协同作用的整体时间，但能够调整它们的幅度，这可以通过质心和压力中心位移的改变来证明。
