Analysis Version
v1
History
Back to Study: Sex differences in absolute and relative changes i...
descriptive
Analysis v1
40
Pro
0
Against

Whether you're new to weightlifting or have been doing it for years, men and women still gain muscle at similar rates compared to each other—experience doesn't change that difference.

Claim Language

Language Strength

association

Uses association language (linked to, correlated with)

The claim uses 'does not significantly moderate,' which indicates a statistical relationship or influence being tested, not a direct cause or certainty. 'Moderate' is an association-level term used to describe how one variable (training experience) affects the strength of another relationship (sex differences).

Context Details

Domain

exercise_science

Population

human

Subject

Resistance training experience (untrained vs. resistance-trained) in healthy young to middle-aged adults

Action

does not significantly moderate

Target

sex differences in absolute or relative muscle hypertrophy

Intervention Details

Type: exercise

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)

40
40

Sex differences in absolute and relative changes in muscle size following resistance training in healthy adults: a systematic review with Bayesian meta-analysis

Systematic Review With Meta-Analysis
Human
2025

This study looked at whether men and women gain muscle differently after lifting weights, and whether it matters if they’re new to lifting or already experienced. It found that experience level doesn’t change the fact that men and women build muscle similarly when you account for their starting size.

Contradicting (0)

0
No contradicting evidence found

Source Study

Sex differences in absolute and relative changes in muscle size following resistance training in healthy adults: a systematic review with Bayesian meta-analysis

Score: 40
DOI: 10.7717/peerj.19042

Similar Assertions

When men and women do strength training, men tend to gain a little more muscle size than women—not because they work harder, but because they usually start with more muscle to begin with.

40
0
87%

When men and women who are healthy and in their 20s to 40s do strength training, they both gain about the same amount of muscle relative to how much they started with—men might gain a tiny bit more, but it’s so small it doesn’t really matter.

40
0
87%

When men and women do strength training, men tend to gain more muscle in their arms and chest than women, but both genders gain about the same amount of muscle in their legs and glutes.

40
0
87%

When older adults (60+) do strength training, men and women gain muscle and get stronger in basically the same way—no big differences between the sexes.

52
0
82%

If you're a guy between 18 and 40 and you start lifting weights, whether you're new to it or have been doing it for years, you probably won't gain much more muscle just because you're experienced—but the people who’ve trained the longest (4+ years) still tend to gain the most muscle, so experience doesn’t always make a clear difference.

0
0
82%