We know muscles stretch less the second time you do a tough workout, but we don’t yet know why that happens.

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Evidence from Studies

Supporting (1)

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Reduced muscle lengthening during eccentric contractions as a mechanism underpinning the repeated-bout effect.

Randomized Controlled Trial

Human

2015 May 15

The study found that after doing the same arm exercise twice, the muscles stretched less the second time—which helped them get less sore and damaged—but it didn’t figure out why the muscles stretched less.

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No contradicting evidence found

Source Study

Reduced muscle lengthening during eccentric contractions as a mechanism underpinning the repeated-bout effect.

Score: 37

DOI: 10.1152/ajpregu.00338.2014

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