Why Lean Body Mass Matters

LBM vs Fat-Free Mass

Lean body mass (LBM) includes everything except fat: muscle, bone, organs, water, and connective tissue. It is typically 1–5% higher than fat-free mass, which excludes essential fats. Both terms are sometimes used interchangeably.

The Boer Formula

The Boer formula is most widely used clinically. Male: LBM = 0.407×weight + 0.267×height − 19.2. Female: LBM = 0.252×weight + 0.473×height − 48.3. Weight in kg, height in cm.

Using LBM for Protein and Supplementation

Protein targets based on LBM rather than total weight are more accurate for people with higher body fat percentages. At 30% body fat, a 100kg person has 70kg LBM — targeting 2g/kg of LBM gives 140g protein, not 200g.

Lean Body Mass Calculator

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