在人类短暂的最大和次最大收缩后,皮质脊髓抑制增加
Alexander D Paish1, Alexander M Zero1, Chris J McNeil2
1Faculty of Health Sciences, School of Kinesiology, The University of Western Ontario, London, Ontario, Canada.
Journal of applied physiology (Bethesda, Md. : 1985)
|August 24, 2023
概括
条件收缩 (CCs) 增加皮质脊髓抑制,以静止期 (SP) 持续时间来衡量. 这项研究发现,最大和次最大的CC都会延长SP,即使次最大收缩导致最小的肌肉强化.
科学领域:
- 神经科学是一个神经科学.
- 发动机控制器的控制器
- 人体生理学 人体生理学
背景情况:
- 跨磁刺激 (TMS) 后的沉默期 (SP) 是皮层脊髓抑制的衡量标准.
- 强化条件收缩 (CCs) 已被证明可以增加SP持续时间,这表明肌肉强化和皮质脊柱抑制之间存在联系.
研究的目的:
- 调查肌肉强化是否是CCs增加皮质脊髓抑制 (SP持续时间) 的先决条件.
主要方法:
- 十名健康成年人接受了最大和次最大的自愿和电气引起的CCs.
- 通过抽力变化来评估肌肉的强化.
- 在CCs之前和之后的亚最大收缩期间 (25% MVC) 使用TMS测量SP持续时间.
主要成果:
- 在最大CCs (81.2%) 后,动力显著增加,但在次最大CCs (3.2%) 后,动力最小.
- 在最大 (12.6%) 和次最大 (4.8%) CCs之后,SP持续时间显著增加.
- 在CC后的抽力 (强度) 和SP持续时间之间没有发现显著的相关性.
结论:
- 皮质脊髓抑制,如SP持续时间所示,在CCs之后增加,无论肌肉强化的程度如何.
- 肌肉收缩的程度,而不是强化本身,可能是影响肌肉 afferents (Ia 和 Ib) 调节皮质脊髓抑制的反的关键因素.
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