Abstract
BACKGROUND AND OBJECTIVES: Resistance training is widely recommended for managing sarcopenia, but evidence on optimal prescriptions remains limited. This study aimed to assess the effects of different resistance training prescriptions on strength, function, and muscle mass in older adults with sarcopenia. METHODS: We searched PubMed, Embase, Web of Science, and CENTRAL to June 2025. Eligible studies were RCTs in adults aged ≥ 60 with sarcopenia, comparing resistance training with usual care or no intervention, and reporting outcomes on strength, physical function, or muscle mass. Risk of bias was assessed using RoB 2. Meta-analyses were conducted using the meta package in R, and Bayesian dose-response models were fitted using the brms package. RESULTS: Twenty-four randomized controlled trials involving 951 participants were included. Random-effects model showed that resistance training significantly improved handgrip strength, gait speed, knee extension strength, timed up and go test (TUG) and and five-times sit-to-stand test (5STS) performance. However, no significant improvements were observed in the short physical performance battery (SPPB), appendicular skeletal muscle mass index and appendicular skeletal muscle mass. Subgroup analyses revealed significant differences across resistance type, frequency, and setting, although meta-regression identified no significant sources of heterogeneity. A nonlinear Bayesian random-effects model suggested an optimal dose of 1220 MET-min/week for improving handgrip strength, while a minimal effective dose of 600 MET-min/week may suffice to achieve clinically meaningful improvements in gait speed. CONCLUSION: Resistance training probably improves muscle strength and physical function in older adults with sarcopenia. However, improvements in grip strength, gait speed, TUG, 5STS, and SPPB did not exceed their MID thresholds, indicating little to no clinical benefit. Resistance type and training frequency were key effect modifiers. Individualized resistance programs within the optimal dose range, emphasizing higher frequency and appropriate resistance types, may help optimize outcomes.