Research

Mixed

Resistance training load (intensity) does not significantly impact skeletal muscle hypertrophy, provided sets are performed to or near volitional fatigue.

You do not need to lift heavy weights to build muscle. Whether you use light weights for many reps or heavy weights for few reps, muscle growth is similar as long as you work close to failure. This allows you to choose loads that feel good for your joints.

ModerateRefutesMEDIUM confidence
We discovered that... there was insufficient evidence in favor of RT load impacting skeletal muscle mass.
Jonathan C. Mcleod et al. · Journal of sport and health science/Journal of Sport and Health Science · 2023

Why this rating

Based on 4/8 reviews providing some or sufficient evidence that load impacts strength, but 4/7 reviews providing insufficient evidence for mass.

Source

The influence of resistance exercise training prescription variables on skeletal muscle mass, strength, and physical function in healthy adults: An umbrella review

Jonathan C. Mcleod et al. · Journal of sport and health science/Journal of Sport and Health Science · 2023

DOI 10.1016/j.jshs.2023.06.005

Meta-analysis · 44 studiesCited 145×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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