Fat-Free Mass Calculator
Calculate fat-free mass and evaluate cellular metabolically active tissue
Input Parameters
Real-time calculation updates dynamically as you adjust inputs. Values remain strictly local on your device.
Fat-Free Mass (FFM)Active Metabolic Tissue
68kg
150 lbs
Adipose Mass
12kg
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: Fat-Free Mass Subtraction
FFM = Weight × [1 - (BodyFat / 100)]Computes non-adipose component used directly in Cunningham and Katch-McArdle metabolic calculations.
Model Assumptions
- Two-compartment body composition model
Variables & Standard Units
| Symbol | Physiological Meaning | Unit |
|---|---|---|
| Weight | Total body mass | kg |
Scientific Limitations
- Does not isolate bone mineral density from muscle tissue
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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