Age causes a redistribution of joint torques and powers during gait
Age causes a redistribution of joint torques and powers during gait
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DOI：
10.1152/jappl.2000.88.5.1804
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发表时间：
2000-05-01
影响因子：
3.3
通讯作者：
Hortobagyi, T
中科院分区：
文献类型：
--
作者：
DeVita, P;Hortobagyi, T
在自行选择的步行速度，老年人相比，年轻人产生的关节扭矩和功率在下肢减少。这些差异可能是实际的步态限制因素和随年龄增长的神经肌肉适应，或者只是有意识地选择运动模式以产生较慢的步态。这项研究的目的是比较年轻人和老年人以相同速度行走时的关节扭矩和功率。12名老年人和14名年轻人（69岁和21岁）在被录像时以1.48米的速度走过一个力平台。根据反作用力和运动学数据计算髋关节、膝关节和踝关节的扭矩和功率。支撑扭矩计算为三个关节扭矩之和。在站立和积极的工作在每个关节的伸肌角冲动来自扭矩和功率。与青年人相比，老年人的步长短4%，步频高4%（均P < 0.05）。两组之间的支撑角冲量几乎相同，但老年人与年轻人相比，髋关节的角冲量增加58%，做功增加279%，膝关节的角冲量减少50%，做功减少39%，踝关节的角冲量减少23%，做功减少29%（t检验，均P < 0.05）。年龄导致了关节扭矩和功率的重新分配，当以相同的速度行走时，老年人比年轻人使用更多的髋关节伸肌，而使用更多的膝关节伸肌和踝关节跖屈肌。沿着运动和感觉功能的减少，衰老的自然史导致运动表现的功能位点的转移。
At self-selected walking speeds, elderly compared with young adults generate decreased joint torques and powers in the lower extremity. These differences may be actual gait-limiting factors and neuromuscular adaptations with age or simply a consciously selected motor pattern to produce a slower gait. The purpose of the study was to compare joint torques and powers of young and elderly adults walking at the same speed. Twelve elderly and fourteen young adults (ages 69 and 21 yr) walked at 1.48 mis over a force platform while being videotaped. Hip, knee, and ankle torques and powers were calculated from the reaction force and kinematic data. A support torque was calculated as the sum of the three joint torques. Extensor angular impulse during stance and positive work at each joint were derived from the torques and powers. Step length was 4% shorter and cadence was 4% higher in elderly adults (both P < 0.05) compared with young adults. Support angular impulse was nearly identical between groups, but elderly adults had 58% greater angular impulse and 279% more work at the hip, 50% less angular impulse and 39% less work at the knee, and 23% less angular impulse and 29% less work at the ankle compared with young adults (t-test, all P < 0.05). Age caused a redistribution of joint torques and powers, with the elderly using their hip extensors more and their knee extensors and ankle plantar flexors less than young adults when walking at the same speed. Along with a reduction in motor and sensory functions, the natural history of aging causes a shift in the locus of function in motor performance.