圆心和偏心肩部旋转力之间的长度-张力差异
Kevin A Giordano1,2, Molly Cich3, Gretchen D Oliver3
1Creighton University Department of Physical Therapy, Phoenix, Arizona.
Journal of strength and conditioning research
|January 23, 2024
概括
异常收缩通常比同心收缩产生更多的力,但长度-张力关系对不同肌肉长度的肩膀旋转强度产生不同的影响. 这项研究强调,异动力学峰值强度值可能不准确地反映所有关节角度的真实肌肉力量能力.
科学领域:
- 生物力学 生物力学
- 运动生理学 运动生理学
- 运动科学 运动科学 运动科学
背景情况:
- 异常的肌肉收缩通常会产生比同心收缩更大的力.
- 长度-张力关系对同心转动与偏心转动的比较力产生的影响仍然不完全理解.
研究的目的:
- 为了比较一个连续90度的运动范围内的同心和偏心肩部外部和内部旋转的强度.
- 为了研究长度-张力关系如何影响肩部旋转期间的力产生.
主要方法:
- 52名身体活跃的人参与了这项研究.
- 通过90度的弧度在前面和肩膀平面上测量了同动力同心和偏心肩膀外部和内部旋转强度.
- 统计参数映射用于分析受试者集中和偏心收缩之间的差异.
主要成果:
- 异常的外部旋转扭矩在特定范围内超过同心扭矩 (30°-90°) 在正面平面和 (30°-90°) 在头骨平面.
- 同心的外部旋转扭矩大于较短肌肉长度的异常扭矩 (5°-15°前部,5°-20°脚).
- 在两个平面的各种范围中观察到同心和偏心内部旋转之间的扭矩产生差异,偏心在中间范围通常显示较高的扭矩,而同心在极端 (前臂水平和末端范围).
结论:
- 异性峰值强度值可能不代表同样的肌肉长度,既集中和偏心收缩,谨慎对所有关节角度的直接比较.
- 在肩部旋转的末端范围下,偏心力产生的减少会影响肩部的稳定性.
- 教练,临床医生和研究人员在解释异动力学强度数据和评估肩部功能时应考虑这些长度-张力差异.
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