When you lift heavy weights versus light weights, your muscles seem to use their different types of fibers in about the same way — at least based on how the muscle’s electrical signal changes during the lift.

24

Pro

0

Against

Evidence from Studies

Supporting (1)

24

Community contributions welcome

24

Myogenic, matrix, and growth factor mRNA expression in human skeletal muscle: Effect of contraction intensity and feeding

Cross-Sectional Study

Human

2013 May

The study found that whether people lifted heavy or light weights, their muscles used the same mix of fiber types, based on a measurement called median power frequency — so the claim is correct.

Contradicting (0)

0

Community contributions welcome

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

Myogenic, matrix, and growth factor mRNA expression in human skeletal muscle: Effect of contraction intensity and feeding

Score: 24

DOI: 10.1002/mus.23667

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