Effects of resistance training on lower-extremity impairments in older people with hip fracture

OBJECTIVE: To study the effects of resistance training on muscle strength parameters, mobility, and balance. DESIGN: Randomized controlled trial. SETTING: Research laboratory and senior gym. PARTICIPANTS: Population-based sample of eligible 60- to 85-year-old community-dwelling men and women 0.5 to 7.0 years after hip fracture. Forty-six people had no contraindications and were willing to participate in the exercise trial. INTERVENTION: Twelve-week intensive progressive strength-power training (n=24), aiming to reduce asymmetric deficit in leg muscle strength and power, or no intervention (n=22). MAIN OUTCOME MEASURES: Isometric knee extension torque (KET) and leg extension power (LEP) measured in the weaker and stronger leg and the asymmetric deficit ([weak/sum both legs]x100%), 10-m walking speed, dynamic balance test, and self-reported outdoor mobility. RESULTS: KET increased in both legs (P <.021), LEP tended to increase in the weaker leg (P=.071), and asymmetric LEP deficit decreased (P=.010) after training compared with the control group. LEP of the stronger leg, asymmetric KET deficit, walking speed, and balance performance were not significantly affected by training. Self-reported ability to walk outdoors improved after training. The compliance to the training was over 90%, and few adverse events (n=4; mainly musculoskeletal) were likely to be caused by the training. CONCLUSIONS: Intensive resistance training is feasible for people with a hip fracture and improved muscle strength and power. More intensive training especially for the weaker leg may be needed to obtain more marked effects on asymmetric deficit, mobility, and balance. Also, the timing and duration of training program should be considered. (ISRCTN identifier ISRCTN34271567.