Lean Body Mass Information

Lean body mass (LBM) is a part of body composition that is defined as the difference between total body weight and body fat weight. This means that it counts the mass of all organs except body fat, including bones, muscles, blood, skin, and everything else. While the percentage of LBM is usually not computed, it on average ranges between 60-90% of total body weight. Generally, men have a higher proportion of LBM than women do.

Lean Body Mass Formulas for Adults

The Boer Formula:

For males: eLBM = 0.407W + 0.267H - 19.2

For females: eLBM = 0.252W + 0.473H - 48.3

The James Formula:

For males: eLBM = 1.1W - 128(W/H)²

For females: eLBM = 1.07W - 148(W/H)²

The Hume Formula:

For males: eLBM = 0.32810W + 0.33929H - 29.5336

For females: eLBM = 0.29569W + 0.41813H - 43.2933

Lean Body Mass Formula for Children

The Peters Formula:

eECV = 0.0215·W^0.6469·H^0.7236

eLBM = 3.8·eECV

In the formulas above, W is the body weight in kilogram and H is the body height in centimeter.