PURPOSE

Deficient muscle-specific strength has been recognized as a key component of sarcopenia. However, the impact of various interventions on muscle-specific strength has not been systematically reviewed.

This study aims to provide a systematic summary of research examining the effects of exercise, nutrition, and other interventions on muscle-specific strength in older adults.

METHODS

Randomized controlled trials (RCTs) were identified through comprehensive searches of major databases. Eligible studies included adults aged 60 years or older, with interventions lasting at least 8 weeks.

Studies were required to assess muscle strength normalized by muscle mass. Standardized mean differences (SMDs) were calculated using random-effects meta-analyses, and heterogeneity was evaluated using I² statistics.

RESULTS

A total of 41 RCTs with 3,141 participants were included in the analysis.

Interventions included resistance exercise, nutritional supplementation, aerobic exercise, concurrent training, combined exercise and nutrition, caloric restriction, and other therapies. Resistance exercise significantly improved muscle-specific strength (SMD = 0.61, 95% confidence interval: 0.27 to 0.94), although heterogeneity was observed (I² = 81%).

In contrast, interventions such as aerobic exercise, concurrent training, combined exercise and nutrition, and nutritional supplementation did not lead to significant improvements in muscle-specific strength. High heterogeneity was observed across all included studies.

CONCLUSIONS

Resistance exercise is the most effective intervention for improving muscle-specific strength in older adults.

The effects of other interventions, such as nutritional supplementation and aerobic exercise, remain inconclusive. Further well-designed RCTs exploring diverse exercise regimens and nutritional interventions are needed to confirm these findings and identify the most effective strategies for enhancing muscle-specific strength in older populations.