OBJECTIVE: Examine the slow passive stretch and release characteristics of the calf muscles of older women with limited dorsiflexion range of motion. DESIGN: A cross-sectional comparative design. BACKGROUND: The passive stretch and release characteristics of the calf muscles of older women with limited dorsiflexion range of motion have not been studied. METHODS: Fifteen older women (mean 79 years) with active dorsiflexion < or =10 degrees and 15 younger women (mean 24 years) without limited dorsiflexion were tested. The right ankle was stretched from plantarflexion to maximal dorsiflexion and released into plantarflexion at 5 degrees /s with minimal surface EMG activity in the soleus, gastrocnemius, and tibialis anterior muscles. Length, passive-elastic stiffness and stored passive-elastic energy were examined. RESULTS: The older women had less maximal passive dorsiflexion, a greater initial stretch angle, and less angular change than the younger women (P < 0.05). The maximal passive resistive force (Newtons) of the stretch phase, and the stored passive-elastic energy ( degrees N) during both stretch and release phases were also less (P < 0.001). The older women had greater passive-elastic stiffness at 0 degrees and 5 degrees of dorsiflexion (P < 0.001). CONCLUSIONS: The older women had decreased calf muscle length, extensibility, maximal passive resistive force, stored passive-elastic energy, but greater angle-specific-stiffness at 0 and 5 degrees of passive dorsiflexion. RELEVANCE: Older women with limited dorsiflexion range of motion have decreased calf muscle length, passive resistive forces and stored passive-elastic energy that may impact static and dynamic standing balance activities. Greater passive-elastic stiffness within their ambulatory dorsiflexion range of motion may partially compensate for the deficits.
OBJECTIVE: Examine the slow passive stretch and release characteristics of the calf muscles of older women with limited dorsiflexion range of motion. DESIGN: A cross-sectional comparative design. BACKGROUND: The passive stretch and release characteristics of the calf muscles of older women with limited dorsiflexion range of motion have not been studied. METHODS: Fifteen older women (mean 79 years) with active dorsiflexion < or =10 degrees and 15 younger women (mean 24 years) without limited dorsiflexion were tested. The right ankle was stretched from plantarflexion to maximal dorsiflexion and released into plantarflexion at 5 degrees /s with minimal surface EMG activity in the soleus, gastrocnemius, and tibialis anterior muscles. Length, passive-elastic stiffness and stored passive-elastic energy were examined. RESULTS: The older women had less maximal passive dorsiflexion, a greater initial stretch angle, and less angular change than the younger women (P < 0.05). The maximal passive resistive force (Newtons) of the stretch phase, and the stored passive-elastic energy ( degrees N) during both stretch and release phases were also less (P < 0.001). The older women had greater passive-elastic stiffness at 0 degrees and 5 degrees of dorsiflexion (P < 0.001). CONCLUSIONS: The older women had decreased calf muscle length, extensibility, maximal passive resistive force, stored passive-elastic energy, but greater angle-specific-stiffness at 0 and 5 degrees of passive dorsiflexion. RELEVANCE: Older women with limited dorsiflexion range of motion have decreased calf muscle length, passive resistive forces and stored passive-elastic energy that may impact static and dynamic standing balance activities. Greater passive-elastic stiffness within their ambulatory dorsiflexion range of motion may partially compensate for the deficits.
Authors: Richard L Gajdosik; Darl W Vander Linden; Peter J McNair; Tammy J Riggin; Jeff S Albertson; Danita J Mattick; Joseph C Wegley Journal: Eur J Appl Physiol Date: 2005-07-20 Impact factor: 3.078