When people eat way less food and exercise a lot for a few days, their body lowers the hormones that help build muscle and raises the stress hormone, which may explain why their muscles stop growing even if they eat protein.

32

Pro

0

Against

Evidence from Studies

Supporting (1)

32

Community contributions welcome

32

Protein synthesis signaling in skeletal muscle is refractory to whey protein ingestion during a severe energy deficit evoked by prolonged exercise and caloric restriction

Randomized Controlled Trial

Human

2019 Apr

The study put overweight men on a very low-calorie diet with lots of exercise and found their body’s fat-burning and muscle-building hormones changed in the exact way the claim says — less testosterone and insulin, more cortisol — and their muscles stopped responding well to protein, meaning they couldn’t build muscle as easily.

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

Protein synthesis signaling in skeletal muscle is refractory to whey protein ingestion during a severe energy deficit evoked by prolonged exercise and caloric restriction

Score: 32

DOI: 10.1038/s41366-018-0174-2

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