Training for muscle power in older adults: effects on functional abilities.

The purpose of this study was to determine the influence of simple, progressive lower body exercise training, focusing on strength and power, on functional abilities in frail older adults. Twenty-five residents of a long-term care facility (75-94 yrs) participated in this randomized controlled trial of 10-wks duration. The exercise group (Ex, n = 18) underwent simple, progressive lower body resistance exercises, specifically aimed at improving muscle power, 3 times/wk; the control subjects (Con, n = 7) maintained their usual daily activities. Knee extensor strength and power were measured on an isokinetic dynamometer (180 degrees/s), and functional performance was assessed from a 6-m walk timed test, a 30-s chair stand, and an 8-ft up-and-go timed test, before and after the 10-wk intervention period. Significant increases were found in the Ex group for eccentric (44%) and concentric (60%) average power (p < 0.05), and improvements were seen on each functional test: the 8-foot up-and-go, chair stand, and walk time improved by 31%, 66%, and 33%, respectively (p < 0.05). No significant change occurred in the Con group. In conclusion, simple progressive exercise training, even in the 10th decade, increases muscle power and is associated with an improved performance of functional activities using the trained muscles.