When women who haven't trained before do weightlifting for 6 weeks, their fast-twitch muscle fibers change: some decrease while others increase, and this happens no matter how fast or hard they train.

41

Pro

0

Against

Evidence from Studies

Supporting (1)

41

Community contributions welcome

41

Early-phase muscular adaptations in response to slow-speed versus traditional resistance-training regimens

Randomized Controlled Trial

Human

2012 Oct

The study looked at women doing different types of weight training and found that all of them reduced one type of muscle fiber and increased another, just like the claim said, even though some methods worked a bit better than others.

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

Early-phase muscular adaptations in response to slow-speed versus traditional resistance-training regimens

Score: 41

DOI: 10.1007/s00421-012-2339-3

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