Physical activity improves strength, balance and endurance in adults aged 40–65 years: a systematic review

QuestionCan physical activity in adults aged 40–65 years enhance strength and balance and prevent falls?DesignSystematic review with meta-analysis of randomised clinical trials.ParticipantsHealthy adults aged 40–65 years.InterventionPrograms that involved the performance of any physical activity in community settings and workplaces.Outcome measuresStrength, balance, endurance, and falls rate.ResultsTwenty-three eligible trials were identified and 17 of these were pooled in the meta-analyses. The meta-analysis of strength outcomes found a moderate effect of physical activity on strength (SMD=0.54, 95% CI 0.38 to 0.70). Larger effects were observed from programs that specifically targeted strength (SMD=0.68, 95% CI 0.49 to 0.87), when compared to those that did not (SMD=0.32, 95% CI 0.09 to 0.55). This difference was statistically significant (effect of strength in meta-regression p=0.045). Physical activity also had a moderate effect on both balance (SMD=0.52, 95% CI 0.24 to 0.79) and endurance (SMD=0.73, 95% CI 0.50 to 0.96). No trials reported effects of physical activity on falls soon after receiving the intervention. A statistically non-significant effect on falls 15 years after receiving a physical activity intervention was found in one trial (RR=0.82, 95% CI 0.53 to 1.26).ConclusionsThis review found that muscle strength, balance, and endurance can be improved by physical activity in people aged 40–65 years. There were bigger effects on muscle strength from programs that used resistance exercises, indicating the need to include a resistance training component if strength enhancement is the goal