运动单元发射率在青春期前的青少年中增加,在线性周期化抵抗运动训练训练后
Trent J Herda1,2, Elizabeth A Holmes3, Christopher J Cleary4
1Department of Health, Sport, and Exercise Science, University of Kansas, 1301 Sunnyside Avenue, Room 101BE, Lawrence, 66045, KS, USA. t.herda@ku.edu.
European journal of applied physiology
|April 18, 2024
概括
在青少年中,抵抗运动训练 (RET) 通过提高运动单元 (MU) 发射率来提高同位体强度,而不是肌肉大小或EMG振幅. 这些发现强调了MU适应是儿童力量增强的关键.
科学领域:
- 神经肌肉生理学 神经肌肉生理学
- 儿科运动科学 儿科运动科学
- 运动医学 运动医学
背景情况:
- 青春期前的青少年对训练表现出独特的神经肌肉反应.
- 了解肌肉功能的适应是优化青少年运动发展的关键.
- 线性周期化阻力运动训练 (RET) 是一种常见的训练模式.
研究的目的:
- 为了研究8周线性周期化RET程序对青春期前儿童神经肌肉功能的影响.
- 为了评估在RET后异位强度,肌肉激活和运动单元 (MU) 行为的变化.
- 确定肌肉截面面积 (CSA) 的变化是否有助于增强力量.
主要方法:
- 25名青春期前青少年 (9.1±0.8岁) 被分配到RET (n=17) 或对照 (n=8) 组.
- 神经肌肉评估包括对称最大自愿收缩 (MVCs) 和次最大收缩 (35%,60% MVC).
- 使用表面电肌图 (EMG) 和来自横向巨的运动单元 (MU) 分解来分析肌肉激活和MU发射特性.
主要成果:
- 在训练后的RET组中,同度强度显著增加 (P=0.006).
- 没有观察到腿部延伸器/屈曲器EMG振幅或肌肉CSA.的显著变化.
- 门较高的MU显示了更高的射击率 (在60%的MVC时更高的y拦截;在35%的MVC时更少的负倾斜).
结论:
- 在青春期前的青少年中,抵抗运动训练会导致力量的提高.
- 这些强度增长主要是通过动力单元 (MU) 发射特征的适应,而不是肌肉大小或整体EMG振幅的变化.
- 运动单元的招募和射击速度调节是增强发育儿童肌肉力量生产的关键机制.
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