Fit Body ScienceEvidence-based fitness analysis

If you're an untrained adult with extra weight, doing resistance training for 12 weeks while eating less—either through intermittent fasting or cutting calories every day—and getting enough protein, gives you similar gains in muscle, strength, and fat loss, no matter which diet approach you pick.

See the scientific wording

In untrained adults with overweight or obesity, a 12-week program of resistance training combined with either 5:2 intermittent fasting or continuous daily energy restriction, while maintaining a protein intake of at least 1.4 g/kg/day, leads to comparable improvements in lean body mass, body weight, fat mass, and upper and lower body strength, indicating that the pattern of energy restriction does not differentially influence whole-body composition or strength outcomes when protein intake and resistance training are equated.

Supporting1 study

Very strong evidence

Randomized trials

One moderate-quality study supports this claim, so treat this as an early signal rather than settled science.

What the research says

1 study reviewed

Supporting (1)

Moderate

Contradicting (0)

None

No contradicting studies found yet

That doesn't mean it's settled — it just means no study has tested the opposite.

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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study

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