If you're already used to lifting weights, doing more sets and reps over time will help you build bigger muscles and get stronger — but only if you keep training consistently.
Evidence from Studies
Supporting (2)
Community contributions welcome
Effects of Different Weekly Set Progressions on Muscular Adaptations in Trained Males: Is There a Dose–Response Effect?
More sets led to bigger strength gains, but muscle growth didn’t clearly improve with more sets—though it might have a little. So, the claim is mostly true for strength, maybe partly true for muscle size.
The Resistance Training Dose Response: Meta-Regressions Exploring the Effects of Weekly Volume and Frequency on Muscle Hypertrophy and Strength Gains.
More lifting sets lead to bigger muscles and stronger muscles, even if the gains slow down after a point—this study proves it by analyzing lots of past experiments.
Contradicting (2)
Community contributions welcome
MODERATE RESISTANCE TRAINING VOLUME PRODUCES MORE FAVORABLE STRENGTH GAINS THAN HIGH OR LOW VOLUMES DURING A SHORT‐TERM TRAINING CYCLE
More lifting doesn’t always mean stronger results — this study found that lifters who did a medium amount of training got stronger than those who did the most or the least.
Evidence of a Ceiling Effect for Training Volume in Muscle Hypertrophy and Strength in Trained Men - Less is More?
More lifting didn’t make trained guys stronger or bigger — in fact, lifting less (5–10 sets a week) worked just as well or better than lifting a lot (15–20 sets).
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.