Optimizing prescription of resistance training for body composition, muscle strength, and physical performance in older adults with sarcopenia: a systematic review and meta-analysis

OBJECTIVE: This systematic review and meta-analysis aimed to address key gaps in understanding the role of resistance training (RT) as an intervention to mitigate age-related sarcopenia. Specifically, it examined: (i) effects on body composition and physical performance; (ii) moderating influences of age and training intensity; and (iii) the presence of a dose-response relationship within the FITT-VP framework. METHODS: A comprehensive search of multiple databases identified randomized controlled trials (RCTs) evaluating RT in older adults with sarcopenia. Data on body composition, muscle strength (MS), and functional performance were extracted. Moderator analyses assessed the impact of participant and intervention characteristics, and meta-regression was performed to explore dose-response patterns. RESULTS: Twenty-five RCTs involving 1,302 participants were included. RT produced significant improvements in MS (ES = 0.71), lean mass (LM, [ES = 0.22]), fat mass (FM, [ES = - 0.17]), walking ability (WA, [ES = 0.41]), grip strength ([GS, [ES = 0.55]), muscle quality (MQ, [ES = 1.25]) (all p < 0.05), but this large effect size was based on only two studies and requires caution interpretation. Dose-response meta-regression revealed a significant non-linear relationship between total RT duration and functional gains, with optimal estimated cumulative volumes of ~ 2,716 min for WA. CONCLUSION: RT is a robust, evidence-based strategy for enhancing MS, functional performance, and body composition in sarcopenic older adults. Findings suggest approximate cumulative duration ranges (~ 1,043 min for MS and ~ 2,716 min for WA) that were associated with maximal gains in pooled analyses. These values should be interpreted as exploratory indicators supporting individualized programming within the FITT-VP framework. Clinicians and exercise practitioners should tailor intensity (60-80% 1RM), frequency, and progression to optimize adherence, effectiveness, and long-term functional outcomes in sarcopenia management.