Research

Energy balance

Physical activity increases weight loss when combined with moderate diet restriction, but adds no benefit when combined with severe diet restriction.

If you are cutting calories moderately (500-700 kcal deficit), adding exercise will help you lose more weight than dieting alone. However, if you are on a very strict, severe diet, adding exercise won't give you extra weight loss benefits because your body adapts metabolically. Stick to moderate restriction if you want to maximize the benefit of exercise.

WeakConditionalHIGH confidence
PA will increase weight loss if diet restriction is modest but not if diet restriction is severe (i,e., <kcalIwkj1 needed to meet RMR).
Joseph E. Donnelly et al. · Medicine & Science in Sports & Exercise · 2009

Why this rating

Categorized as Evidence Category A.

Source

Appropriate Physical Activity Intervention Strategies for Weight Loss and Prevention of Weight Regain for Adults

Joseph E. Donnelly et al. · Medicine & Science in Sports & Exercise · 2009

DOI 10.1249/mss.0b013e3181949333

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DOI resolved against Crossref · corpus check 2026-06-10

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