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随着收缩强度的增加,梯形状的兴奋分布会发生变化,但反复收缩不会发生变化
Kara-Lyn Harrison1, Zachariah Henderson1, Josée Rochon1
1Integrative Musculoskeletal Research Lab, University of Manitoba, Faculty of Kinesiology and Recreation Management, Winnipeg, Manitoba, Canada.
概括
上梯形 (UT),中梯形 (MT) 和下梯形 (LT) 的肌肉刺激模式因收缩强度而异. 这些肌肉采用不同的神经肌肉策略,特别是UT和LT,在适应增加的努力时.
科学领域:
- 生物力学和运动控制
- 肌肉骨生理学 肌肉骨生理学
- 人类运动科学科学 人类运动科学
背景情况:
- 上梯形 (UT) 肌肉刺激模式适应疼痛,疲劳和重复收缩.
- 肌肉刺激分布的变化被假设是为了减轻肩部疼痛和病理.
- 在不同的收缩强度期间,中 (MT) 和下梯形 (LT) 刺激变化的作用尚不清楚.
研究的目的:
- 调查UT,MT和LT肌肉的激发分布是否不同.
- 为了比较异位收缩期间的激发分布,在最大自愿异位收缩 (MVIC) 的30%和60%处.
- 评估激发分布的变化,以60%的MVIC重复收缩.
主要方法:
- 高密度电肌图 (EMG) 用于记录19名参与者的肌肉活动.
- 参与者在亚最大强度 (30%和60%的MVIC) 和重复性收缩时进行了同位数收缩.
- 使用统计参数映射 (SPM) t测试和重心分析来评估激发分布变化.
主要成果:
- 刺激分布随着UT (∼92%),LT (∼70%),MT (∼14%) 的收缩强度增加而显著变化.
- 在重复收缩期间,没有观察到任何梯形肌的兴奋分布的显著变化.
- 巴里中心分析没有显示肌肉激发的整体中心的显著变化.
结论:
- UT,MT和LT肌肉表现出不同的神经肌肉策略,以应对不同的收缩强度.
- 肌肉刺激的重新分配主要发生在收缩强度增加时,而不是在重复收缩时.
- 这些发现突出了形肌群在功能任务期间的不同区域激活模式.
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