If young men lift weights for 15 weeks, their arm muscles get bigger—about 10–12% for the whole muscle and 9–24% for the individual muscle fibers—no matter if their body’s hormone levels spike during workouts or stay normal.

45

Pro

0

Against

Evidence from Studies

Supporting (1)

45

Community contributions welcome

45

Elevations in ostensibly anabolic hormones with resistance exercise enhance neither training-induced muscle hypertrophy nor strength of the elbow flexors.

Randomized Controlled Trial

Human

2010 Jan

The study had guys do arm workouts for 15 weeks, some with extra leg exercises to boost hormones and some without. Both groups got just as much stronger and their muscles grew just as much—so hormones didn’t matter. This matches the claim that muscle growth happens even if hormones don’t spike.

Contradicting (0)

0

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No contradicting evidence found

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.

Source Study

Elevations in ostensibly anabolic hormones with resistance exercise enhance neither training-induced muscle hypertrophy nor strength of the elbow flexors.

Score: 45

DOI: 10.1152/japplphysiol.01147.2009

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