The relationship between the model estimates of FFM and FM is linear.

<p>A) Body composition based on modeling DXA-derived data of the full DXA population (IG + CV) using anthropometric variables exhibits a linear relationship between FM and FFM (red line). The anthropometric model of Weltmann <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0024017#pone.0024017-Weltman1" target="_blank">[13]</a>, derived from hydrostatic weighing in a similar obese female population, is similar (black line). In contrast, data obtained by Forbes <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0024017#pone.0024017-Forbes3" target="_blank">[23]</a> for a female population using isotopic dilution methodology is non-linear (blue line). B) The FFM/FM ratio approaches unity for body mass greater than 100 kg.