通过在骑自行车时应用的逆侧和逆侧实验性疼痛来研究皮质运动和神经肌肉功能的调节
Jenny Zhang1, Niloofar Honarvar1, Arezou Habibirad2
1Faculty of Kinesiology, University of Calgary, Calgary, Canada.
Scandinavian journal of medicine & science in sports
|August 26, 2025
概括
实验性疼痛通过增加感知到的努力和疲劳而损害了运动耐力. 然而,它不会影响神经肌肉功能,但可以根据疼痛改变皮质抑制.
科学领域:
- 运动生理学
- 神经科学
- 疼痛研究
背景情况:
- 疼痛可能会对运动表现产生负面影响.
- 在长时间的运动中,实验性疼痛对运动控制的具体影响尚不完全理解.
- 调查疼痛对皮质脊髓刺激性和抑制性的影响至关重要.
研究的目的:
- 测试运动或非运动四肢的实验性疼痛是否会调节神经肌肉功能,皮质脊髓刺激性和抑制性.
- 确定长时间循环时疼痛是否会加剧感知和心肺呼吸反应.
- 通过详尽的实践来研究这些效应的时间流程.
主要方法:
- 十个健康的成年人经历了三次单腿骑自行车,以达到60%的峰值功率:控制 (没有疼痛),对侧疼痛 (CONTRA) 和ipsilateral疼痛 (IPSI).
- 用每5分钟一次的跨磁刺激 (TMS) 来评估皮质脊髓刺激 (MEP·Mmax-1) 和皮质内抑制 (SICI,LICI).
- 记录了最大的自愿收缩 (MVC),自愿激活和感知/心肺呼吸反应.
主要成果:
- 与对照组相比,在CONTRA和IPSI条件下,失效时间显著减少.
- 在不同条件下,MVC力,自发激活力和静止力没有差异.
- 短间隔内皮抑制 (SICI) 在CONTRA增加,而长间隔内皮抑制 (LICI) 在CONTRA增加,但在IPSI下降. 在这两种疼痛条件下,疼痛感知,疲劳和劳动力评级都更高.
结论:
- 在长时间骑行时,实验性疼痛会增强感知反应 (疲劳,努力),导致耐力减弱.
- 尽管有疼痛,神经肌肉功能 (MVC,自愿激活) 仍然完好无损.
- 疼痛应用的位置差异调节皮质抑制,暗示复杂的中枢神经系统适应.
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