OBJECTIVE: To investigate the effect of muscle strength exercise training (MSET) on lean mass (LM) gain and muscle hypertrophy in older patients with lower limb osteoarthritis (OA).
METHODS: A comprehensive search of online databases was performed until April 20, 2019. Randomized controlled trials (RCTs) that reported the effects of MSET on LM, muscle thickness, and cross-sectional area (CSA) in older patients with OA were identified. A risk of bias assessment and meta-analysis were performed for the included RCTs.
RESULTS: We included 19 RCTs with a median PEDro score of 6 (range: 3-7) out of 10. In total, 1195 patients (65% women, 85% with knee OA) with a mean age of 62.1 (range: 40-86) years were analyzed. MSET resulted in significantly higher LM gain (standard mean difference [SMD]: 0.49; 95% confidence interval [CI]: 0.28, 0.71; P < 0.00001) than did the nonexercise controls. Meta-analysis results revealed significantly positive effects of MSET on muscle thickness (SMD: 0.82; 95% CI: 0.20, 1.43; P = 0.009) and CSA (SMD: 0.80; 95% CI: 0.25, 1.35; P = 0.004) compared with nonexercise controls. No significant effects in favor of MSET were observed for any muscle outcome compared with exercise controls. Five RCTs reported nonsevere adverse events in response to MSET, whereas no RCTs reported severe events.
CONCLUSION: MSET is effective in increasing LM and muscle size in older adults with OA. Clinicians should incorporate MSET into their management of patients at risk of low muscle mass to maximize health status, particularly for older individuals with OA.