Evaluation of Percent Body Fat Estimates Using Different Body Composition Methods in Recreationally Active Adults Across Both Sexes

This thesis compared percent body fat (%BF) values derived from different body composition (BC) modalities: air displacement plethysmography (Bod Pod), skinfold (SKF) prediction equations (Durnin and Womersley (DW), Jackson and Pollock (JP7), (JP3) and Yuhasz) with dual-energy x-ray absorptiometry (DXA) as the reference and compared whether they differed by sex. Utilizing data from 38 active individuals (20 females, aged 26.3±4.0 years; 18 males, aged 30.5±7.4 years), females demonstrated significant differences between all modalities with DXA (P<0.05), except for DW equations. Males demonstrated no significant differences with DXA (P<0.05), except for the Yuhasz equation. Bland-Altman (B-A) analyses found significant systematic biases (P<0.05) in females and males with magnitudes of difference ranging from -2.0% to -10% and -1.4% to -4.0%, respectively vs DXA. Significant proportional biases between different modalities and DXA were also evident in both sexes. These results highlight the importance of using the most appropriate BC approach to estimate %BF.