Differences In Body Composition Analysis Between Underwater Weighing, Dual-energy X-ray Absorptiometry, And Two Bioelectrical Impedance Devices In Overweight Young Adults

Abstract

PURPOSE: As the prevalence of obesity rises, as does the need for reliable body composition (BC) methods. Many methods of BC analysis exist, however accuracy is questioned with respect to which criterion method is referenced by the device. There is often debate within the scientific literature about which criterion method and BIA field measurement is applicable for the overweight population. Little research has been found comparing two debated criterion methods with field methods in overweight or obese individuals. The purpose of this study is to compare criterion methods, hydrostatic weighing (HW) and dual energy x-ray absorptiometry (DXA) with two methods of bioelectrical impedance analysis (BIA) in overweight or obese young adults to determine the validity of these methods. METHODS: N=25 overweight and obese adults (BMI 29.04 ± 3.568kg/m2, 13 males, 12 females, ages 24.37 ± 4.924y) followed standardized pre-testing guidelines for BC assessment. Percent body fat (%BF) was estimated by Omron BIA, Impedimed BIA and compared to GE Lunar Prodigy DXA, and HW. %BF was estimated using generalized population specific equations. RESULTS: Repeated measures ANOVA with a Greenhouse-Geisser correction determined there was a significant mean difference between BC methods. Pairwise comparisons indicated significant differences (p<0.05) between Omron BIA and Impedimed, Omron BIA and DXA, and between HW and DXA. Furthermore, %BF was significantly correlated between Omron BIA and HW (p<0.05, r=0.902) as well as between Impedimed BIA and DXA (p<0.05, r=0.709). CONCLUSIONS: The results of this study show criterion methods, HW and DXA were found to be statistically different from one another. Depending upon which criterion method is referenced, the appropriate field measurement Omron BIA or Impedimed BIA should be selected.