在人类快速收缩期间,局部温度对运动单元行为的影响
Kazutaka Ota1, Hikaru Yokoyama2, Kazushige Sasaki3
1Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan. gotham1731@g.ecc.u-tokyo.ac.jp.
European journal of applied physiology
|May 2, 2025
概括
局部肢体冷却可以提高运动单元的招募和放电速度,从而对快速收缩过程中扭矩发展 (RTD) 的速度产生积极影响. 这项研究阐明了温度对神经肌肉功能的影响.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 人类运动科学科学 人类运动科学
- 运动生理学 运动生理学
背景情况:
- 扭矩发展速度 (RTD) 对快速运动至关重要.
- 温度显著影响生理过程,包括肌肉功能.
- 肢体局部温度对动力单位在动态收缩过程中的行为所产生的特定影响尚不清楚.
研究的目的:
- 为了研究局部肢体温度对运动单元行为的影响.
- 为了确定温度变化如何影响在快速异面收缩期间扭矩发展 (RTD) 的速度.
- 阐明不同热条件下的电机单元特征和RTD之间的关系.
主要方法:
- 十个健康的雄性将下肢浸泡在三种温度 (10°C,33°C,43°C) 的水中,持续20分钟.
- 参与者进行了最大自发性收缩 (MVC) 和快速持久的同度背部屈曲收缩.
- 记录了前节的高密度表面电肌图,并将其分解为动力单元尖列车.
主要成果:
- 晚期RTD (0-150毫秒) 在冷条件下显着较低,即使正常化为MVC扭矩.
- 在招募时,机动单元的排放率在寒冷 (51.4 pps) 和热 (42.0 pps) 条件下更高.
- 招聘门随着温度的下降 (冷: 23.9%,中性: 29.2%,热: 36.2%的MVC),与RTD变化相关.
结论:
- 局部冷却导致较早的动力单元招聘和更高的排放率.
- 在冷却过程中这些动力单元的调整有助于减轻扭矩发展速度的减少.
- 肢体温度是影响神经肌肉控制的关键因素,在快速的力量产生过程中.
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