Calf muscle-tendon properties and postural balance in old age

作者：Gladys Leopoldine Onambélé-Pearson, Marco Vincenzo Narici, Constantinos N. Maganaris · 发表于：Journal of Applied Physiology · 年份：2006 · DOI：10.1152/japplphysiol.01442.2005 · 被引用次数：361 · 研究领域：Balance, Gait, and Falls Prevention、Effects of Vibration on Health、Cerebral Palsy and Movement Disorders

We tested the hypothesis that compromised postural balance in older subjects is associated with changes in calf muscle-tendon physiological and mechanical properties. Trial duration and center of pressure (COP) displacements were measured in 24 younger (aged 24+/-1 yr), 10 middle-aged (aged 46+/-1 yr), and 36 older (aged 68+/-1 yr) healthy subjects under varying levels of postural difficulty. Muscle-tendon characteristics were assessed by dynamometry, twitch superimposition, and ultrasonography. In tandem and single-leg stances, trial duration decreased (<or=65% lower, P<0.001) and COP displacements increased (<or=90% higher, P<0.05) with age. Muscle strength, size, activation capacity, and tendon mechanical properties decreased with age by 55, 13, 13, and 36-48%, respectively (P<0.05). Regressions with these parameters and balance indexes were significant (P<0.05) for single-leg and tandem (0.69<r2<0.90) postures only, indicating that the age-related changes in muscle-tendon characteristics may explain the majority of the variance in balance performance during tasks more difficult than habitual bipedal stance.