在动力力场适应过程中,协同激活的肌肉运动单元活动的变化
Yori R Escalante1, Shancheng Bao1, Yuming Lei1
1Program of Motor Neuroscience, Department of Kinesiology & Sport Management Texas A&M University, College Station, TX, 77843.
Journal of neurophysiology
|May 7, 2025
概括
运动适应通过调整运动单元 (MU) 控制在激动肌肉 (而不是对抗肌肉) 中来减少肌肉合收缩. 这种策略在新任务中提高了运动准确性和稳定性.
科学领域:
- 神经科学是一个神经科学.
- 发动机控制器的控制器
- 生物力学 生物力学
背景情况:
- 肌肉共同收缩对于运动适应,减少错误和在新的动态环境中保持关节稳定至关重要.
- 了解适应过程中同激活肌肉内的运动单元 (MU) 活动变化至关重要,但尚未得到充分研究.
研究的目的:
- 在运动适应过程中,研究三手臂 (激动体) 和两手臂 (对抗体) 内运动单元活动的变化.
- 探索共收缩调制和动力单元控制策略在适应新动态环境中的作用.
主要方法:
- 使用先进的电肌图传感器阵列和信号处理技术.
- 检查了三肌和两肌的运动单元激活在与力场扰乱的达到任务期间.
- 分析了在适应阶段的动力单元招募,振幅和火速变化.
主要成果:
- 随着适应,运动错误减少,速度增加,肌肉协同收缩减少.
- 减少的共同收缩是由三肌活动增加所驱动的,而两肌活动保持不变.
- 运动单元的振幅在两个肌肉中都增加了,但是三肌的MU发射率稳定了,而振幅继续上升,表明了战略的转变.
结论:
- 运动适应过程中减少的共收缩是由改变的运动单元控制策略中介的,主要是在激动性肌肉内.
- 在后来的适应阶段,更多地依赖电机单元的振幅调节而不是火速,可以优化力生产和稳定性.
- 研究结果表明,通过精细的运动单元招募,可以在动态环境中增强运动精度和关节稳定性的机制.
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