Research

Hormonal

Performing resistance training in an energy deficit impairs lean mass gains compared to training in energy balance, but does not impair strength gains.

If you are trying to lose weight while lifting weights, expect to get stronger but not necessarily bigger. A 500 kcal daily deficit will likely stop you from gaining lean mass, but you will still improve your strength. To maximize muscle growth, you must avoid prolonged energy deficits.

GoodQualifiesHIGH confidence
Analysis A showed LM gains were impaired in RT+ED vs RT+CON (effect size (ES) = −0.57, p = 0.02), but strength gains were comparable between conditions (ES = −0.31, p = 0.28).
Chaise Murphy et al. · Scandinavian Journal of Medicine and Science in Sports · 2021

Why this rating

Meta-analysis of randomized controlled trials with moderate heterogeneity and no significant publication bias.

Source

Energy deficiency impairs resistance training gains in lean mass but not strength: A meta‐analysis and meta‐regression

Chaise Murphy et al. · Scandinavian Journal of Medicine and Science in Sports · 2021

DOI 10.1111/sms.14075

Meta-analysis · 59 studiesCited 53×
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DOI resolved against Crossref · corpus check 2026-06-10

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