After doing strength training, men might see a tiny bit more muscle growth in their slow-twitch muscles than women, but we’re not super sure because the studies were small and measured muscle samples in different ways.
Claim Language
Language Strength
probability
Uses probability language (may, likely, can)
The claim uses 'slightly favors' and 'findings are uncertain'—phrases that indicate likelihood rather than certainty. 'Slightly favors' suggests a probable trend, not a guaranteed outcome, and 'uncertain due to high variability' reinforces probabilistic language rather than definitive causation.
Context Details
Domain
exercise_science
Population
human
Subject
Type I muscle fiber hypertrophy following resistance training
Action
favors
Target
males
Intervention Details
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.
Evidence from Studies
Supporting (1)
Sex differences in absolute and relative changes in muscle size following resistance training in healthy adults: a systematic review with Bayesian meta-analysis
This study found that when men and women do strength training, men’s slow-twitch muscle fibers grow a tiny bit more than women’s — just like the claim says — but the difference is small and not super clear because not all studies were the same.