<P> A reasonably accurate estimation of body fat can be obtained by means of a "two compartment model" of the human body which is based upon two simplifying assumptions: 1 . Human fat has a density of 0.9 grams / ml, and 2 . The lean (non-fat) components of the human body have an overall density of 1.1 grams / ml . </P> <P> The two compartment model allows for an estimation of the proportions of fat and lean components of the body to be made from the overall body density . And, as explained above, the overall body density (Db) is easily calculated from body mass and body volume . Rearranging the equation of fractional densities to solve for the proportion of fat (f) will yield the following equation: </P> <Dl> <Dd> f = 495 / D b − 450 (\ displaystyle f = 495 / Db - 450) </Dd> </Dl> <Dd> f = 495 / D b − 450 (\ displaystyle f = 495 / Db - 450) </Dd>

The body uses the same proportion of nutrients for all types of exercise