What body recomposition is#
Recomposition means losing fat and building muscle in the same period — staying at roughly the same bodyweight while your composition shifts. It happens when training provides a strong growth stimulus and nutrition provides just enough energy: the body draws on fat stores to cover a small deficit while directing protein toward new muscle.
Who it works best for#
Recomp potential is highest for new lifters, people returning after a layoff, and anyone carrying meaningful body fat — in these situations the muscle-building signal is strong enough to run alongside fat loss. Experienced, already-lean lifters recomp very slowly; for them, dedicated building and cutting phases usually produce faster total progress. The verdict line above applies exactly this logic to your training status and body fat.
The three levers#
- Calories: eat at maintenance or a slight deficit — 100–200 kcal under. Deep deficits kill the muscle-building side of the equation.
- Protein: 2.2 g per kg of bodyweight per day, at the high end of the evidence-based range, supports both sides at once. If you know your body fat percentage, 2.2 g per kg of lean mass is the sharper dose — it avoids over-prescribing protein for the fat you are trying to lose.
- Progressive overload: the non-negotiable. Without training that pushes weights and reps up over time, a small deficit is just a slow diet.
Why body fat percentage changes the math#
Without a body fat number, this calculator uses the Mifflin-St Jeor equation, which infers your metabolic rate from height, weight, age, and sex. Give it a body fat percentage and it switches to Katch-McArdle — 370 + 21.6 × lean mass in kg — which reads your energy needs off the tissue that actually burns the calories. For people well above or below average body fat, that is the more accurate of the two. Estimate yours with the Navy tape method if you do not have a number.
Training-day and rest-day calorie cycling#
A flat daily target is perfectly effective, but many lifters prefer to put more food where the work is: more on lifting days to fuel training and recovery, less on rest days to keep the weekly average on target. The table above does that arithmetic for you, using the training days implied by your activity level, so the seven-day total still lands on your recomp number. How far each day sits from maintenance depends on how many days you train — with six training days a week there is little room to move, so the swing is small.
Two rules keep it honest. Hold protein constant every day — muscle does not need less on rest days. And shift carbohydrates rather than fat between day types, since carbs are what fuel hard sets and fat is what keeps hormones happy.
How to know it is working#
The scale is nearly useless during recomp — weight can hold still for months while composition changes underneath. Judge progress by strength trends and tape measurements instead: waist shrinking while lifts climb is recomposition working. Gript charts your lifts automatically and tracks body measurements — weight, body fat, and thirteen body parts — so both signals live in one place.