When you do a single tough workout like running or cycling, your muscles produce more of two specific tiny molecules called miR-1 and miR-133a—but if you train like that regularly over weeks or months, those same molecules go down. It’s like your muscles hit a reset button after long-term training.

Evidence from Studies

Supporting (0)

0

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No supporting evidence found

Contradicting (1)

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20

Epigenetic changes in healthy human skeletal muscle following exercise– a systematic review

Systematic Review

Human

2019 Jul

The study talks about how exercise changes tiny molecular markers in muscle, but it doesn’t say whether these specific markers (miR-1 and miR-133a) go up after one workout and down after weeks of training, so we can’t tell if the claim is right or wrong.

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

Epigenetic changes in healthy human skeletal muscle following exercise– a systematic review

Score: 20

DOI: 10.1080/15592294.2019.1614416

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