What this calculator measures
Body recomposition — gaining muscle while losing fat — is achievable but slower and less obvious on the scale than a dedicated cut or bulk. It is best suited to beginners, returning trainees, or those returning from a break, where the body's sensitivity to both protein and training stimulus is elevated.
How this calculator works
This calculator uses a small 5% calorie deficit from maintenance combined with a high protein target of 2.1 g/kg body weight — the key nutritional conditions for supporting muscle protein synthesis while in a slight energy deficit. The approach is supported by ISSN protein research on body composition during energy restriction.
How to use your result
Measure progress with multiple methods — body fat percentage, waist measurements, strength levels, and photos — rather than scale weight alone. The scale may barely move during effective recomposition as fat mass falls while muscle mass rises. Allow 8–16 weeks for meaningful results. If progress stalls completely, consider a short dedicated cut or bulk phase.
Important limitation
Calculator results are estimates. Pregnancy, eating disorders, medical conditions, injuries, or concerning symptoms require qualified professional guidance.