发动机单元发射速度和角的性别相关差异
Michael J Marsala1, Alicia M Kells1, Anita D Christie1
1Faculty of Health Sciences, School of Kinesiology, Western University, London, ON, Canada.
概括
男性的运动单元发射率 (MUFR) 和角比女性更高,尽管这些差异与肌肉结构无关. 随着收缩强度的增加,MUFR和pennation角度增加,但带的长度没有变化.
科学领域:
- 运动生理学 运动生理学
- 生物力学 生物力学
- 肌肉生理学 肌肉生理学
背景情况:
- 了解神经肌肉控制中的基于性别的差异对于优化训练和康复至关重要.
- 发动机单元发射速度 (MUFR) 和肌肉结构,如角和带长度,是肌肉力量生产的关键决定因素.
- 以前的研究表明,这些参数中存在潜在的性别差异,但它们的相互关系仍然不清楚.
研究的目的:
- 为了同时研究在同位数收缩过程中运动单元发射速度 (MUFR) 和肌肉结构性质 (角,束长度) 的性别相关差异.
- 检查收缩强度对MUFR和男性和女性肌肉结构的影响.
- 确定不同性别和强度的MUFR和肌肉结构性质之间的关系.
主要方法:
- 30名参与者 (16名女性,14名男性) 在最大自愿收缩 (MVC) 的20-100%时进行了同度背部屈曲.
- 动力单元的发射速度 (MUFR) 通过使用表面电肌学分解来评估.
- 用超声波测量肌肉纤维角和带长度.
主要成果:
- 与女性相比,男性的平均MUFR,笔纹角和带长度显著更高.
- 平均MUFR和角都随着收缩强度的增加而增加,而带的长度保持一致.
- 在两性中均未发现平均MUFR与角或带长度之间的显著相关性.
结论:
- 尽管在MUFR和肌肉结构中观察到与性别相关的差异,但这些因素似乎没有直接关联.
- 收缩强度调节了MUFR和角,但不是带长度,以性别一致的方式.
- 这些发现表明,MUFR的性别差异可能受到超出研究的肌肉结构特性之外的因素的影响.
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