增加干部质量在下楼过程中引起下肢生物机械可塑性
Alexis K Nelson1, Hailey Fong2, Alexander M Carnall2
1Interdisciplinary Biomedical Sciences Program, University of Tennessee Health Science Center, Memphis, TN, USA.
International journal of exercise science
|August 31, 2023
概括
在下楼时增加体重会增加下肢的负面作用,主要是在脚. 关节工作的这种转变表明脚补偿了增加的质量,减少了膝关节的贡献.
科学领域:
- 生物力学 生物力学
- 人类运动科学科学 人类运动科学
- 运动生理学 运动生理学
背景情况:
- 下楼梯是日常生活中的常见活动.
- 了解身体质量如何影响生物力学对于预防伤害和表现至关重要.
- 之前的研究已经探索了移动过程中的关节负荷,但增加的质量对楼梯下降关节工作的特定影响需要进一步调查.
研究的目的:
- 为了研究模拟的体重变化对下肢关节工作和相对关节贡献在楼梯下降的影响.
- 量化增加负荷 (5-20%的体重) 对脚,膝盖和关节功率和下楼过程中的工作的影响.
主要方法:
- 十名健康的大学年龄的参与者在五种负载条件下进行了楼梯下降试验 (0%,5%,10%,15%,20%的体重).
- 用六度自由模型计算了脚,膝盖和部的三维关节力量.
- 斜面平面关节的工作是通过整合关节功率从最初的接触到脚的时间来计算的.
主要成果:
- 增加增加的体重显著增加了楼梯下降期间的下肢负面工作总量 (p < 0.001).
- 脚负面关节的工作增加了增加的质量.
- 关节对下肢总体工作的相对贡献增加,而膝关节的相对贡献减少 (p = 0.014,p = 0.006).
结论:
- 模拟的体重增加改变了下肢生物力学在楼梯下降.
- 脚关节在吸收能量 (负面工作) 中发挥着更大的作用,因为增加的质量增加.
- 膝关节对负面工作的贡献在下楼过程中随着体重增加而减少,这表明了补偿策略.
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