独立的神经驱动和不同的运动单元在腿筋肌肉的释放特征在等比膝盖曲
Chrysostomos Sahinis1, Ioannis G Amiridis2, Dario Farina3
1Laboratory of Neuromechanics, Department of Physical Education and Sport Sciences at Serres, Aristotle University of Thessaloniki, Agios Ioannis, 62110, Serres, Greece. sachinic@phed-sr.auth.gr.
European journal of applied physiology
|September 4, 2025
概括
半肌 (ST) 和双腿肌 (BF) 的运动单元 (MU) 排放模式在膝盖角度不同. 这些独特的神经驱动突显出需要肌肉特异性训练策略以获得最佳性能.
科学领域:
- 神经肌肉生理学
- 生物力学
- 运动科学
背景情况:
- 了解运动单位 (MU) 控制对于优化肌肉功能和训练至关重要.
- 半肌 (ST) 和双腿肌 (BF) 在膝盖曲中起着关键作用,但它们的独特神经控制机制尚未完全阐明.
- 肌肉长度受到膝关节角度的影响,可以显著影响肌肉力量的产生和运动单元的活动.
研究的目的:
- 研究和比较半肌 (ST) 和双腿肌 (BF) 中的运动单元 (MU) 的排放特征.
- 检查这些MU排放模式如何在不同的膝关节角度 (0°,45°和90°) 变化,代表不同的肌肉长度.
- 评估ST和BF肌肉在同位数收缩过程中的神经驱动和协调.
主要方法:
- 十五名健康的男性在三个膝关节角度进行以最大自发收缩率 (MVC) 的10-60%的同度膝关节屈曲收缩.
- 使用高密度电肌图 (EMG) 来记录肌肉活动,并将信号分解以确定MU放电时间.
- 计算了关键的MU排放特征,包括平均排放率 (MDR) 和变异性 (CoV ISI,fCST的SD). 通过过累积尖峰列车 (fCST) 的交叉相关性来评估神经驱动协调.
主要成果:
- 最长的肌肉长度 (膝盖角0°) 的最大自发收缩力 (MVC),中间长度 (45°) 的扭矩稳定性最差.
- 双腿骨 (BF) 显示出更高的平均排泄率 (MDR) 和更大的神经驱动可变性 (fCST 的 SD),而半骨 (ST) 则显示出更高的排泄率可变性 (CoV ISI).
- ST和BF神经驱动之间的低交叉相关性表明独立的肌肉控制. ST的神经驱动的可变性与BF的扭矩稳定性有更强的关系.
结论:
- 运动单元放电特征和神经驱动在半肌 (ST) 和双腿肌 (BF) 之间表现出不同的模式.
- 这些差异因膝关节的角度而异,表明每个肌肉在不同的长度上都有独特的神经控制策略.
- 这些发现强调了考虑肌肉特异性适应和训练方案以增强膝关节曲功能的重要性.
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