After a tough leg workout, a blood marker of muscle damage (CK) spikes by more than 1.5 times and stays high for two days, showing the muscles are still healing.

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Evidence from Studies

Supporting (1)

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Recovery after Heavy Resistance Exercise and Skeletal Muscle Androgen Receptor and Insulin-Like Growth Factor-I Isoform Expression in Strength Trained Men

Cohort Study

Human

2011 Mar

The study found that after intense weight training, a marker of muscle damage (creatine kinase) went up in the blood for at least two days — which means the muscles were still getting repaired, just like the claim says.

Contradicting (0)

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No contradicting evidence found

Source Study

Recovery after Heavy Resistance Exercise and Skeletal Muscle Androgen Receptor and Insulin-Like Growth Factor-I Isoform Expression in Strength Trained Men

Score: 30

DOI: 10.1519/jsc.0b013e318202e449

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