How this calculation works
The Boer and Hume equations use different fitted coefficients. Both operate on height and weight, so a difference between results illustrates how the model choice affects an estimate.
Each equation estimates lean mass as a weight coefficient × kg + a height coefficient × cm − a profile-specific intercept.A worked example
With the male equations, 80 kg and 180 cm gives 61.42 kg by Boer and about 57.79 kg by Hume.
Good to know
Adult population equations for educational estimates. Lean mass includes organs, water and other tissue. Use a clinically appropriate assessment for care or medication dosing.
Reference: Boer, estimated lean body mass study (opens in a new tab) ↗
How the inputs affect the result
Keep units in kilograms and centimetres. An implausible result can come from a unit mistake or measurements outside a population where the equation is appropriate.
Changing the equation profile changes the fitted coefficients.
Where the calculation applies
Adult population equations for educational estimates. Lean mass includes organs, water and other tissue. Use a clinically appropriate assessment for care or medication dosing.
For a related calculation, see the Historical Navy circumference body fat calculator.
Read more: Boer, estimated lean body mass study (opens in a new tab) ↗
A few questions, answered
Why are both estimates different even with the same inputs?
The equations were fitted with different methods and populations. Each has a different weighting of height and body weight.
What does the “Female equation example” setting illustrate?
Changing the equation profile changes the fitted coefficients.