The Claim

Twelve weeks of resistance training increases biceps brachii muscle cross-sectional area by approximately 12.7%, from 11.8 ± 2.7 cm² to 13.3 ± 2.6 cm², as measured by MRI in a subset of eight college men.

Source: Muscle fiber hypertrophy, hyperplasia, and capillary density in college men after resistance training.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
31score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Quantitative
1 study reviewed
In plain English

Lifting weights for three months can make the upper arm muscle about 13% bigger in young college guys.

See the scientific wording

Twelve weeks of resistance training increases biceps brachii muscle cross-sectional area by approximately 12.7%, from 11.8 ± 2.7 cm² to 13.3 ± 2.6 cm², as measured by MRI in a subset of eight college men.

What the research says

1 study

  1. Study: Muscle fiber hypertrophy, hyperplasia, and capillary density in college men after resistance training.

    The study looked at the same type of workout and measured the same muscle growth in the same kind of people, and found exactly what the claim says: biceps got bigger by about 12.7% after 12 weeks of training.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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