在青春期前的男孩和女孩中,肘部曲器的强度,肌肉大小和动力臂
Louise E Wood1, Sharon Dixon2, Chris Grant3
1Department of Sport and Exercise Science, University of Portsmouth, St. Michael's Building, White Swan Road, Portsmouth, PO1 2DT, UK.
Pediatric exercise science
|August 17, 2024
概括
在青春期前的儿童中,肌肉的大小和杆在性别之间没有差异. 肌肉截面面积 (CSA) 是影响肘部屈曲强度的关键因素,解释了超过50%的扭矩变异.
科学领域:
- 儿科运动科学 儿科运动科学
- 人类生物力学
- 儿童发展 儿童发展
背景情况:
- 了解影响儿科力量的因素对于生长和发育至关重要.
- 肘部曲扭矩是儿童上肢强度的关键指标.
- 以前的研究还没有完全阐明肌肉大小和杆在儿童力量发展中的相互作用.
研究的目的:
- 调查前青春期儿童的肘部屈曲扭矩,肌肉横截面积 (CSA) 和杆的性别差异.
- 为了确定肘部 flexor 肌肉 CSA,时刻臂长度和等比扭矩之间的关系.
- 为了建立儿童强度变化的基线数据.
主要方法:
- 38名青春期前儿童 (平均年龄9.6岁) 在三个关节角度 (10°,50°,90°) 进行了对称肘部曲动作.
- 使用磁共振成像 (MRI) 来测量肘部 flexor (EF) 肌肉的CSA和手臂的长度.
- 统计分析检查了性别差异和强度,CSA和杆之间的相关性.
主要成果:
- 在男孩和女孩之间,没有发现肘部屈曲扭矩,肌肉CSA或时刻臂长的显著差异.
- 肘部曲肌肉CSA与肘部曲50°和90°的等比扭矩成正比.
- 肌肉CSA占同度扭矩差异的4757%,而时刻臂长度解释了90°的扭矩差异的19%.
结论:
- 肌肉大小是前青春期儿童肘部曲强度的主要决定因素,独立于性别.
- 杆在调节扭矩方面起到次要作用,特别是在更大的关节角度.
- 这些发现为了解童年期间的力量发展和变化提供了必要的基线数据.
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