模拟表明,以减少推进力的步行不会减轻下肌硬性的能量后果
Richard E Pimentel1, Gregory S Sawicki2,3, Jason R Franz1
1Joint Department of Biomedical Engineering, UNC Chapel Hill and NC State University, Chapel Hill, North Carolina, United States of America.
PloS one
|October 26, 2023
概括
老龄化会减少肌的硬性和推开力,增加步行成本. 这项研究没有发现这些因素之间的相互作用,这表明策略应该针对肌硬度或独立的推开力,以减少代谢成本.
科学领域:
- 生物力学 生物力学
- 人体生理学 人体生理学
- 老年学是一门学科.
背景情况:
- 衰老会对肌肉骨结构和行走功能产生负面影响.
- 肌硬度 (kT) 和推开力 (FP) 影响行走的代谢成本,并随着年龄的增长而降低.
- 肌刚性和推开力与步行成本相关的相互作用尚未得到充分理解.
研究的目的:
- 调查与年龄相关的功能变化 (减少FP) 是否减轻结构变化 (减少KT) 的代谢成本.
- 检查肌刚性和推开力对行走代谢成本的独立和相互作用影响.
主要方法:
- 在年轻成年人中使用生物反在强度感应跑步机上对推开力 (FP) 的实验性操纵.
- 个性化肌肉骨系统的计算建模,在生理范围内的肌硬度 (kT) 有所变化.
- 模拟不同kT和FP组合的单个肌肉代谢成本.
主要成果:
- 肌硬度 (kT) 和推力 (FP) 独立地影响行走的代谢成本.
- 较高的kT和偏离典型FP增加了代谢成本.
- 没有证据表明kT和FP之间的相互作用对年轻成年人的总代谢成本在固定的速度.
- 观察到复杂的,肌肉特异性的代谢反应;例如,减少KT和FP增加了总成本,但减少了三肌肌肉的成本.
结论:
- 减少推开力并不能缓解走路时下肌硬化的代谢后果.
- 可穿戴设备和康复可以针对肌刚性或推开力,以减少与年龄相关的行走代谢成本的增加.
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