中部和外围神经肌肉疲劳后的坡道和快速的最大自发同度收缩
Benjamin Dalton1, Garrett Hester1, Michaela Alesi1
1Wellstar College of Health and Human Services, Kennesaw State University, Kennesaw, GA, United States.
Frontiers in physiology
|September 4, 2024
概括
与快速收缩相比,斜坡收缩更明显地损害了早期的快速扭矩和肌肉激活. 周围和中心疲劳反应相似,但快速收缩增加了皮质脊髓抑制.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 运动科学 运动科学
- 发动机控制器的控制器
背景情况:
- 最大自愿同度收缩 (MVICs) 是一种常见的疲劳方法,但扭矩发展速度对疲劳的影响还未得到充分研究.
- 在上坡和快速MVIC之间存在运动指挥和神经肌肉激活的差异,这表明疲劳和潜在机制的潜在变化.
研究的目的:
- 为了比较坡道与快速MVIC对最大和快速扭矩产生的影响.
- 为了研究相应的神经肌肉和皮质脊髓变化后,这些疲劳的协议.
主要方法:
- 十二名健康的男性进行了间歇性 MVIC 膝盖延伸器,使用 2 秒的升级 (RAMP) 或爆炸式升级 (RAPID),直到峰值扭矩减少 50%.
- 在每个条件之前和之后评估了最大和快速的扭矩,外围疲劳 (抽参数),中心疲劳 (自愿激活),快速肌肉激活和皮质脊髓刺激性.
主要成果:
- 在RAMP和RAPID条件下,最大扭矩和晚期快速扭矩均降低.
- 早期快速扭矩能力 (0-50毫秒) 和快速肌肉激活在RAMP条件下显著地受损.
- 外周疲劳和神经引起的自愿激活在条件之间是相似的,而RAPID增加了皮质脊髓抑制.
结论:
- 与快速的MVIC相比,Ramp MVICs更严重地损害了早期的快速扭矩能力和肌肉激活.
- 周围和中心疲劳反应在很大程度上是可比的,但快速的MVICs诱导了更大的皮质脊髓抑制.
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