Research

Energy balance

Intermittent diet breaks (one week of energy balance every two weeks) during a 25% energy deficit do not improve body composition or resting metabolic rate compared to continuous energy restriction in resistance-trained females.

If you are a resistance-trained woman, taking one-week diet breaks every two weeks during a 25% calorie deficit will not help you lose fat or preserve muscle any better than dieting continuously for the same total time in deficit. You can use breaks if you psychologically need them, but do not expect them to save your metabolism or muscle mass compared to sticking to the deficit continuously.

GoodRefutesHIGH confidence
Thus, diet breaks do not appear to induce improvements in body composition or metabolic rate in comparison with continuous energy restriction over six weeks of dieting...
Madelin R. Siedler et al. · Journal of Human Kinetics · 2023

Why this rating

Randomized controlled trial with resistance-trained females, though short duration (6-8 weeks).

Source

The Effects of Intermittent Diet Breaks during 25% Energy Restriction on Body Composition and Resting Metabolic Rate in Resistance-Trained Females: A Randomized Controlled Trial

Madelin R. Siedler et al. · Journal of Human Kinetics · 2023

DOI 10.5114/jhk/159960

rct · n=38Cited 8×
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DOI resolved against Crossref · corpus check 2026-06-10

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