Normalized FFMI & Natural Muscle Potential Calculator
Body Mass Index (BMI) fails to distinguish between body fat and skeletal muscle. The Fat-Free Mass Index (FFMI per Kouri et al., 1995) isolates your lean mass and normalizes it to a baseline height of 1.80m for objective comparison.
1. Biological Sex
2. Max Natural Weight (Target BF%)
Body Composition Science & Anthropometry
Peer-reviewed research on natural muscular hypertrophy ceilings.
Clinical Journal of Sport Medicine: Empirical landmark study demonstrating that a normalized FFMI of ~25.0 represents the statistical natural limit for elite drug-free strength athletes.
Validates anthropometric frame adjustments based on wrist and ankle girth to calibrate personal genetic ceiling projections.
What is the difference between raw FFMI and normalized FFMI? +
Due to geometric scaling (the cube-square law), taller individuals naturally possess higher raw FFMI values. Kouri's equation normalizes values to an even 1.80m baseline for fair comparison across heights.
Can natural lifters exceed a normalized FFMI of 25? +
A normalized FFMI of 25 represents the empirical upper ceiling for drug-free individuals in the Harvard study. Rare genetic outliers may occasionally reach 25.0 to 25.5 naturally.
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MaGymus handles all these calculations automatically in the background of your workouts: auto warm-up pyramids, deterministic Epley progression, 11-dimensional RP plan audits, FFMI curves, and multi-gym machine normalization โ 100% offline on your iPhone.