Research

Hormonal

Intermittent Energy Restriction (IER) involving alternating periods of energy restriction with refeeds may preserve resting energy expenditure (REE) and fat-free mass (FFM) better than Continuous Energy Restriction (CER) during weight loss, though evidence in athletes is currently limited.

If you are an athlete struggling with plateaus or extreme hunger on a standard diet, try adding 'refeed' days where you eat at maintenance or slightly above. This might help preserve your muscle and keep your metabolism from slowing down as much as it would on a constant low-calorie diet. However, be aware that direct proof in athletes is still scarce, so monitor your progress closely.

LimitedQualifiesLOW confidence
An IER regime alternating five days of ER with twice-weekly refeeds was superior to CER in preserving REE... and FFM... among resistance-trained athletes completing seven weeks of ER... In one review, it was reported that alternate-day fasting caused less loss of FFM, with equivalent FM loss when compared to CER in adults with overweight and obesity.
Jackson Peos et al. · Sports · 2019

Why this rating

The paper explicitly states 'evidence for effectiveness of IER in athletic populations is lacking' and relies on a conference abstract and extrapolations from overweight populations.

Source

Intermittent Dieting: Theoretical Considerations for the Athlete

Jackson Peos et al. · Sports · 2019

DOI 10.3390/sports7010022

narrative_reviewCited 31×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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