Why lean mass beats scale weight
Scale weight bundles muscle, fat, glycogen, and water into one misleading number. Lean body mass isolates the tissue that burns calories, supports joints, and predicts long-term function — and it is the metric that should stay flat or rise during a diet.
- • A good cut loses 3 lb of fat for every 1 lb of lean mass at most.
- • Rapid lean-mass drops usually mean glycogen and water, not muscle.
- • Track lean mass monthly, not weekly — measurement noise swamps real change.
FAQ
What is a good FFMI?
Around 18–20 is typical for untrained men, 22–24 indicates serious training, and natural lifters rarely exceed 25. For women, 15–18 covers most trained individuals.
How do I increase lean body mass?
Progressive resistance training, roughly 0.7–1.0 g of protein per pound of body weight, and a small calorie surplus. Gains of 1–2 lb of lean mass per month are realistic for beginners.
Is lean body mass the same as muscle mass?
No. Lean mass includes bone, organs, water, and connective tissue in addition to skeletal muscle, which is roughly half of it.
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