Predicting body composition in college students using the womersley and durnin body mass index equation

When assessing fitness levels, body composition is usually measured. The purpose of this study was to determine the overall efficacy of a body mass index [BM I] equation for predicting body composition with respect to college aged participants. Body composition was measured using dual-energy x-ray absorptiometry [DXA] and was estimated using the Womersley and Durnin BMI prediction equation. There was no significant [P=0.8] percent body fatt [%BF] difference between the BMI prediction equation and DXA [BMI Predicted=25 [10] [min=6; max=52] %PFvs DXA=25 [6] [min=10; max=45] %BF]. In addition, a significant correlation was found between the two approaches [r=0.79l, P=0.001]. However. both the standard error of estimate [6.32%BF] and total error [6.63 %BF] were outside acceptable ranges for prediction equations. The Womersley and Durnin equation for estimating %BF was not found to be a good estimate. Therefore, although the BMI predicted %BF has been previously found to predict skinfold estimated %BF, it does not appear valid in estimating %BF from DXA

estimation of the fat free mass index in athletes

The purpose of this investigation was to compare a practical measurement of fat free mass index [FFMI] from bioelectrical impedance analysis [BIA] to the dual energy X-ray absorptiometry [DEXA] value in collegiate athletes. Thirty-three male baseball players and 16 female gymnasts volunteered to participate in this study during their respective pre-season. Subjects visited the laboratory once and had their measurements taken in the following order: weight, height, DEXA, and Omron HBF-500. The BIA device investigated was not a valid estimate of FFMI when compared to the DEXA. The TE was 0.93 kg/ m[2] for males and 0.78 kg/ m[2] for females. There were also significant mean differences between the BIA prediction and the DEXA value for males [BIA=20.6 kg/m[2] vs. DEXA=21.1 kg/m[2], P=0.007] and females [BIA=16.2 kg/m[2] vs. DEXA=17.5 kg/m[2], P=0.001]. The BIA device investigated in this study did not provide a valid estimate of FFMI in male and female collegiate athletes. Although there was a general tendency for the BIA to underestimate FFMI compared to DEXA, 98% of the estimates were within plus or minus 2 kg/ m[2]. Therefore, while slightly biased, BIA may provide a reasonable [+/- 2 kg/ m[2]] estimate of nutritional status for practitioners who are unable able to afford more expensive equipment