活化后增强和肌肉和神经反应的异步作用
Anthi Xenofondos1,2, Anastasia Papavasileiou2, Eleni Bassa2
1Physical Education and Sport Sciences, Frederick University, Nicosia,Cyprus.
概括
后激活强化显著提高肌肉力量和速度. 然而,峰值扭矩增长与神经变量变化没有直接相关,这表明复杂的增强机制.
科学领域:
- 运动生理学 运动生理学
- 神经肌肉功能 神经肌肉功能
- 肌肉的表现 肌肉的表现
背景情况:
- 后激活强化 (PAP) 是一种现象,在短时间的强烈肌肉活动中,随后的肌肉收缩会增强.
- 了解PAP的潜在机制,特别是肌肉和神经因素之间的相互作用,对于优化训练方案至关重要.
- 这些变化的时间进程和它们在不同个体中的变化仍然需要进一步研究的领域.
研究的目的:
- 调查驱动后激活增强 (PAP) 的机制.
- 分析PAP期间肌肉和神经适应的时间进程.
- 为了确定峰值扭矩增强和神经变量变化之间的关系.
主要方法:
- 十四名训练有素的雄性进行了四组六次6秒的最大等距离足部屈曲.
- 间收缩和间设置间隔分别为15秒和2分钟.
- 测量的变量包括峰值扭矩 (TT),扭矩发展速度,H反射 (H/M),电肌图 (RMS/M) 和自愿激活.
主要成果:
- 在所有套件中观察到峰值扭矩 (TT) 和扭矩发展速度的显著增加.
- 峰值扭矩和半放松时间的时间显著减少,表明肌肉放松的速度更快.
- 虽然发生了峰值扭矩强化,但正常化的H-反射 (H/M) 和EMG (RMS/M) 在最大TT时没有显著变化,但在设置内H/M增加.
结论:
- 一组四次6秒的收缩足以在大多数人中诱导PAP.
- 峰值扭矩强化不总是与测量的神经变量变化保持一致.
- 进一步的研究应该探索PAP反应的时间动态和个体间的变化.
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