Doing more sets of weightlifting each week helps you build more muscle, but after a certain point, adding even more sets gives you less extra benefit.
Scientific Claim
Higher weekly resistance training volume is associated with greater muscle hypertrophy in young, primarily male, trained individuals, with evidence suggesting diminishing returns at higher volumes.
Original Statement
“The posterior probability of the marginal slope exceeding zero for the effect of volume on both hypertrophy and strength was 100%, indicating that gains in muscle size and strength increase as volume increases. However, both best-fit models suggest diminishing returns, with the diminishing returns for strength being considerably more pronounced.”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The study design cannot confirm causation due to unknown randomization in source studies. The phrase 'gains increase as volume increases' implies causation, which is unsupported.
Evidence from Studies
Supporting (1)
The Resistance Training Dose Response: Meta-Regressions Exploring the Effects of Weekly Volume and Frequency on Muscle Hypertrophy and Strength Gains.
More weekly weight training leads to bigger muscles, but after a certain point, adding even more sets gives you less extra gain — and this study proves it with data from thousands of people.