在短期卸载和积极恢复后,神经调节对肌肉力量生产的贡献
Giovanni Martino1, Giacomo Valli1, Fabio Sarto1
1Department of Biomedical Sciences, University of Padova, Padova, ITALY.
Medicine and science in sports and exercise
|May 1, 2024
概括
短期不使用会通过减少运动神经元中的持续向内电流 (PIC) 来降低肌肉力量. 通过恢复PIC水平,抵抗演习完全恢复了力量生成能力.
科学领域:
- 神经科学是一个神经科学.
- 运动生理学 运动生理学
- 肌肉生物学 肌肉生物学
背景情况:
- 神经因素在不使用后显著影响肌肉力量损失.
- 持续向内电流 (PIC) 放大了运动神经元的突触输入,影响了力量的产生.
- 不使用诱导的力量减少背后的特定神经机制仍然不清楚.
研究的目的:
- 调查短期单边下肢悬浮 (ULLS) 是否通过PIC减少神经调节输入.
- 通过恢复神经调节输入来确定体育炼是否可以恢复力量产生能力.
- 阐明中央神经调节在肌肉不使用和恢复中的作用.
主要方法:
- 12名健康成年人接受了10天的ULLS,随后是21天的基于抵抗运动的积极恢复 (AR).
- 最大自发收缩 (MVC) 在ULLS前,后和AR后进行测量.
- 持续的向内电流 (PIC) 估计使用高密度表面电肌学 (EMG) 在升级的同位数收缩期间.
主要成果:
- ULLS显著降低了估计PIC的33% (P < 0.001) 和MVC的29% (P = 0.002).
- 主动恢复完全恢复了PIC (P < 0.001) 和MVC (P = 0.003).
- 在PIC的变化与MVC的变化有显著的相关性 (r = 0.63,P = 0.004).
结论:
- 减少PIC有助于肌肉不使用后的力量损失.
- 阻力练习通过恢复PIC有效地恢复了力量产生能力.
- 中枢神经调节,特别是PIC,是肌肉不使用引起的力量缺陷和运动中介恢复的关键因素.
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