Research

Energy balance

An energy surplus enhances fat-free mass (FFM) gains during resistance training compared to energy balance, but the exact magnitude of the surplus required is unknown and varies by individual.

If you are struggling to gain muscle despite consistent training, try adding a small energy surplus of 1,500-2,000 kJ (approx. 350-480 kcal) per day. Monitor your body composition and strength. If you gain too much fat, reduce the surplus. This is particularly useful for those who find it hard to gain lean mass.

ModerateSupportsMEDIUM confidence
In a preliminary exploration of the combined effects of an energy surplus and resistance training, it was found that only those individuals who consumed an energy dense liquid supplement twice daily on training days observed significant gains in body mass and FFM... over an 8-week training period (57).
Gary Slater et al. · Frontiers in Nutrition · 2019

Why this rating

Supported by preliminary studies and pilot data, but the paper explicitly states there is a 'dearth of research' and no rigorously controlled long-term investigations.

Source

Is an Energy Surplus Required to Maximize Skeletal Muscle Hypertrophy Associated With Resistance Training

Gary Slater et al. · Frontiers in Nutrition · 2019

DOI 10.3389/fnut.2019.00131

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

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