在同度膝关节收缩期间的神经肌肉动力学:目标力,膝关节角度和骨旋转对力稳定的影响
Han Yuan1, Maeng-Kyu Kim2,3
1Department of Physical Education, Graduate School, Kyungpook National University, Daegu, Korea.
Scientific reports
|April 21, 2025
概括
在膝盖延伸期间的神经肌肉控制受到目标力和膝盖角度的影响,影响力稳定性. 虽然骨旋转不会直接影响力稳定性,但它会改变肌肉激活模式,这与力控制和肌肉结构相关.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 生物力学 生物力学
- 运动学 运动学
背景情况:
- 力量稳定 (FS) 对运动控制至关重要,受各种因素的影响,包括力水平,关节角度和肌肉激活.
- 了解肌肉形态,电肌图 (EMG) 信号和FS之间的相互作用,可以了解动态任务中的神经肌肉策略.
研究的目的:
- 为了研究不同的目标力水平,膝关节角度和骨旋转位置如何影响膝关节伸展期间的力稳定性和EMG特征.
- 检查肌肉形态 (厚度,回声强度) 和神经肌肉参数 (FS,EMG稳定性) 之间的相关性.
主要方法:
- 十二名年轻成年男性在不同的目标力 (10-70% MVIC),膝盖角度 (30°,60°,90°) 和部旋转位置 (IR,NR,ER) 上进行了同度膝盖延伸.
- 记录了来自大中,横和大腿直肠的EMG信号,以及力输出.
- 用超声波成像来评估肌肉厚度和回声强度.
主要成果:
- 目标力水平和膝关节的角度显著影响了力稳定性,绝对波动随着力量的增加而增加,相对波动随着力量的增加而减少.
- 骨旋转没有直接影响力稳定性,但显著改变了EMG特征,特别是在60°膝盖角度.
- 在力稳定性和EMG稳定性之间,以及肌肉形态参数 (射频回声强度,四头肌肉厚度) 和EMG变异性之间观察到强烈的相关性.
结论:
- 目标力和膝关节角度是异面膝延伸过程中力稳定的关键决定因素.
- 骨旋转调节神经肌肉激活模式,而不是直接影响力稳定.
- 肌肉形态和EMG变异性之间的关系凸显了它在神经肌肉控制和力量生产效率方面的作用.
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