Effects of Resistance Training Volume on Physical Function, Lean Body Mass and Lower-Body Muscle Hypertrophy and Strength in Older Adults: A Systematic Review and Network Meta-analysis of 151 Randomised Trials.
Level 1 - systematic review of randomized trials
Systematic review and network meta-analysis of randomized controlled trials
PubMed 39405023 · doi:10.1007/s40279-024-02123-z
What was done
This was a systematic review and random-effects network meta-analysis of randomized controlled trials searching multiple databases up to April 2023. The review investigated supervised resistance training in older adults aged 60 years and older. Training volume was categorized into terciles: low (LVRT), moderate (MVRT), and high volume (HVRT), calculated from weekly frequency, exercises, and sets. Primary outcomes were physical function (fast walking speed, timed up and go, 6-minute walk test), lean body mass, lower-body muscle hypertrophy, and lower-body muscle strength (knee extension and leg press 1-RM, isometric strength, isokinetic torque). Program duration (<20 weeks vs ≥20 weeks) and physical health status were evaluated as moderators.
What was found
The analysis included 161 articles describing 151 trials (n = 6306). LVRT was the most effective for timed up and go (SMD -1.20, 95% CI: -1.57 to -0.82), 6-minute walk test (SMD 1.03, 95% CI: 0.33 to 1.73), lean body mass (SMD 0.25, 95% CI: 0.10 to 0.40), and muscle hypertrophy (SMD 0.40, 95% CI: 0.25 to 0.54). MVRT and HVRT were reported as most effective for lower-limb strength (numerical effect sizes omitted in abstract). Only HVRT improved fast walking speed (SMD 0.40, 95% CI: -0.57 to 0.14). Findings were independent of duration and predominantly observed in healthy older adults.
Why it matters
These findings suggest that low-volume resistance training is sufficient for older adults to achieve functional and body-composition benefits, lowering the barrier to exercise adherence, though higher volumes are required to optimize lower-body strength.
Limits
Findings are primarily applicable to healthy older adults, as evidence was limited for physically impaired individuals. Effect size metrics for strength outcomes were not detailed in the abstract, and the reported confidence interval for fast walking speed crosses zero despite the stated efficacy.