Relationship between passive properties of the calf muscles and plantarflexion concentric isokinetic torque characteristics |
| |
Authors: | Gajdosik Richard L |
| |
Institution: | (1) Clinical Kinesiology Laboratory, The Physical Therapy Department, The University of Montana, Missoula, MT 59812–4680, USA, |
| |
Abstract: | The purpose of this study was to use a model of aging to examine the relationships between passive properties of the calf
muscles and plantarflexion concentric isokinetic torque characteristics. Eighty-one active women 20–84 years of age were tested
using a Kin-Com isokinetic dynamometer interfaced with electromyography (EMG). The passive properties were tested by stretching
the muscles from relaxed plantarflexion to a maximal dorsiflexion (DF) angle at a rate of 5°·s–1 (0.087 rad·s–1) with minimal raw EMG activity (<0.05 mV). The maximal concentric torque was tested from maximal passive DF into plantarflexion
at four randomly ordered velocities of 30, 60, 120, and 180°·s–1. Pearson correlation coefficients (Bonferroni adjusted) indicated a hierarchical order of high to moderate positive correlations
between four passive properties and the peak and mean concentric torque for all test velocities. Correlation coefficients
for the four passive properties ranged from 0.50 to 0.78 (P<0.001), and the coefficients of determination (r
2) from higher to lower were: (1) maximal DF passive resistive torque (r
2: 0.50–0.62), (2) length extensibility (r
2: 0.40–0.49), (3) maximal muscle length (r
2: 0.28–0.41), and (4) passive elastic stiffness in the last half of the full-stretch range of motion (r
2: 0.25–0.31). The maximal DF passive resistive torque and the length extensibility accounted for 50–62% and 40–49% of the
variability in the concentric torque, respectively. The results indicate that the concentrically stronger calf muscles of
active women were positively correlated with passively stronger, longer, and stiffer calf muscles, which are characteristics
of the calf muscles of younger women. Further studies are needed to examine whether therapeutic interventions, such as stretching
and strengthening, can promote adaptations in the calf muscles of older women to attain these more youthful characteristics.
Electronic Publication |
| |
Keywords: | Ankle Calf muscles Passive properties Isokinetic strength Women |
本文献已被 PubMed SpringerLink 等数据库收录! |
|