疲劳引起的运动单元行为的变化和膝关节关节位置的肌肉间一致性
Hyeon-Deok Jo1, Maeng-Kyu Kim2
1Sports Science Research Institute, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea.
Gait & posture
|December 6, 2025
概括
神经肌肉疲劳会损害力稳定性,改变运动单元的行为,影响因膝关节关节角度而异. 疲劳引起的运动单元特性和肌肉间连贯性的变化在曲膝盖位置最为明显.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 发动机控制器的控制器
- 运动科学 运动科学
背景情况:
- 神经肌肉疲劳影响力稳定性和运动单元 (MU) 行为.
- 关节角度对神经肌肉对疲劳的反应的影响,特别是MU特征和肌肉间连贯性,尚不清楚.
研究的目的:
- 为了研究疲劳和膝关节角度对MU行为,力量稳定性和在同位平行屈曲过程中肌肉间一致性的影响.
- 为了比较直 (0°) 和曲 (90°) 膝盖位置之间的神经肌肉适应.
主要方法:
- 16名男性在疲劳前和疲劳后的状态下,以不同强度 (30-70% MVIC) 进行了同位体足.
- 疲劳是由持续的收缩引起的. 从单体 (SOL) 和中胃 (GM) 的高密度表面EMG被分析为MU参数 (MUAP,FR,ReTHR,DeTHR).
- 在整个频段中评估了SOL和GM MU尖峰列车之间的肌肉间连贯性.
主要成果:
- 在疲劳后,双膝两位的最大自愿同度收缩减少.
- 疲劳后力量稳定性恶化,特别是在曲膝盖条件下,在更高的强度下.
- 疲劳改变了肌肉特征 (MUAP,FR,ReTHR,DeTHR) 以肌肉特异性和姿势依赖的方式.
- 在疲劳后的曲膝盖状况中,β频段肌肉间连贯性增加.
结论:
- 疲劳会诱导肌肉特异性和姿势依赖的神经肌肉适应.
- 变化MU属性和肌肉间连贯性是显著的,特别是在曲的膝盖位置.
- 关节角在调节神经肌肉对疲劳的反应中起着至关重要的作用.
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