OBJECTIVE: To test the hypothesis that older age significantly affects hip abduction and adduction joint torque-time generating capability in women. DESIGN: Cross-sectional study, wherein subjects were tested in a supported standing position. SETTING: University human performance laboratory. PARTICIPANTS: Seventy-six healthy, adult women (38 young; 38 old). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The dependent variables were peak isometric torque and its corresponding torque rate and average peak isokinetic torque. Age group differences were assessed by analysis of variance. RESULTS: Isometric peak torques were significantly lower in older women (P</=.001) for hip abduction (34%) and adduction (24%). Decreases with age were also significant for isometric rates of torque for both muscle groups (P</=.001). Average isokinetic peak torque of hip abduction and adduction showed even greater declines in older women versus the young (P</=.001) with losses of 44% and 56%, respectively. CONCLUSIONS: The hip abductor and adductor torques showed relatively marked age-related changes. To enhance balance assessment and treatment, and to reduce the risk of falls and related injuries in older women, greater focus should be placed on understanding the role of joint torque-time changes on frontal plane balance control.
OBJECTIVE: To test the hypothesis that older age significantly affects hip abduction and adduction joint torque-time generating capability in women. DESIGN: Cross-sectional study, wherein subjects were tested in a supported standing position. SETTING: University human performance laboratory. PARTICIPANTS: Seventy-six healthy, adult women (38 young; 38 old). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The dependent variables were peak isometric torque and its corresponding torque rate and average peak isokinetic torque. Age group differences were assessed by analysis of variance. RESULTS: Isometric peak torques were significantly lower in older women (P</=.001) for hip abduction (34%) and adduction (24%). Decreases with age were also significant for isometric rates of torque for both muscle groups (P</=.001). Average isokinetic peak torque of hip abduction and adduction showed even greater declines in older women versus the young (P</=.001) with losses of 44% and 56%, respectively. CONCLUSIONS: The hip abductor and adductor torques showed relatively marked age-related changes. To enhance balance assessment and treatment, and to reduce the risk of falls and related injuries in older women, greater focus should be placed on understanding the role of joint torque-time changes on frontal plane balance control.