Methodology
Protein Per Kg of Lean Mass vs Bodyweight, a Worked Example
Francesco Zen, founder of ZTraining · Last updated 19 June 2026
| Scenario | Lean-mass based | Bodyweight based | Gap |
|---|---|---|---|
Why a 30g gap matters more than it sounds
At the smaller end, the difference looks minor on paper. In practice, protein set from total weight is extra digestive load for no real benefit, since lean tissue, not body fat, is what actually uses the protein.
Why the error keeps growing
As body fat percentage rises, the gap between bodyweight and lean mass widens, and so does the error in a bodyweight-based calculation. At 30% body fat, a third of total weight isn't tissue that needs protein at all, yet a bodyweight formula still counts it. The higher the body fat, the worse a bodyweight-based number gets.
Related: How much protein to build muscle · Body-fat threshold rules for building muscle
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