A before-and-after comparison can look different depending on whether it is expressed in absolute size or percentage change. This distinction matters when research on women and men becomes a simplified message about who “responds better” to training.

What the research found

A meta-analysis of 29 studies comparing muscle growth between sexes found broadly similar relative increases. Men tended to show somewhat larger absolute gains, which is a different comparison from percentage change relative to starting muscle size. [1]

Group averages do not predict an individual’s progress. The findings also do not mean every person needs the same exercises, workload or support.

Compare progress with your own starting point

Use consistent measures and a programme suited to your experience. Avoid treating another person’s absolute change as the standard your body must match. The review supports taking women’s capacity for muscle growth seriously rather than building expectations from stereotypes.

Putting it into perspective

An absolute increase starts from the amount of muscle already present; a relative increase expresses change against that starting point. These comparisons can lead to different-looking summaries of the same evidence. Knowing which one a headline uses helps prevent a statistical distinction from becoming a stereotype about training potential.