Input Parameters
Real-time calculation updates dynamically as you adjust inputs. Values remain strictly local on your device.
Normalized FFMIAbove Average
21.8kg/m²
Raw FFMI: 21.7 kg/m²
Lean Body Mass
68.8kg
Fat Mass
11.2kg
Natural Upper Baseline
25.0kg/m²
Kouri et al. empirical natural thresholdFFMI Classification Scale (Men)
16 – 17
Below average muscularity
18 – 19
Average population muscularity
20 – 21
Above average (recreational lifter)
22 – 23
Excellent muscular development
24 – 25
Superior / Near natural genetic ceiling
> 25
Rare naturally / Suspicious for ergogenic aids
Clinical Responsibility Note: This calculation provides statistical estimations for informational and educational purposes only. It is not an individualized medical diagnosis or clinical prescription.
Mathematical Formula & Scientific Methodology
Formula: Normalized Fat-Free Mass Index (Kouri et al. 1995)
Normalized FFMI = [FFM / H²] + 6.1 × (1.8 - H)Normalizes raw FFMI to a standardized stature of 1.8 meters, eliminating height bias in muscularity comparisons.
Model Assumptions
- Accurate body fat percentage measurement
Variables & Standard Units
| Symbol | Physiological Meaning | Unit |
|---|---|---|
| FFM | Fat-free mass | kg |
| H | Height | m |
Scientific Limitations
- Empirical 25.0 ceiling derived primarily from male resistance training cohorts
Peer-Reviewed Scientific Citations
A reanalysis of the factors influencing basal metabolic rate in normal adults: importance of fat-free mass (1980)
Cunningham JJ (1980) — The American Journal of Clinical Nutrition, 33(11), 2372-2374
Key Finding: Demonstrated that lean body mass accounts for nearly all variance in basal metabolic rate between sexes and ages.
Frequently Asked Questions
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