A Pilot Study of Within-Day Variation in Bioelectrical Impedance Analysis of Body Fat in College Men and Women
Bioelectrical impedance analysis (BIA) has become a popular technique for measuring body fat (%fat). The purpose of this study was to determine the within-day variability and significant difference among selected BIA devices. Four men and three women were measured in early morning and late afternoon for urine specific gravity (Usg) to determine hydration and on 6 commercially available BIA devices to estimate %fat. Although afternoon Usg was slightly higher (1.024 ± 0.021 g/cm3) than morning Usg (1.018 g/cm3), they were not significantly different. There was a significant difference among BIA devices but not significant difference between morning (22.5 ± 9.4%) and afternoon (20.5 ± 8.7%) estimate of %fat. Correlations between morning and afternoon %fat measures ranged from r = 0.63 to r = 1.00. Results suggest that while various BIA devices may give different estimates of %fat, the values should not vary greatly depending on time of day.
Keywords: Body Fat, Bioelectric Impedance Analysis, BIA, %fat, Hydration, Body Composition
Topic(s):Exercise Science
Health Science
Presentation Type: Poster
Session: 5-7
Location: GEO - SUB
Time: 3:30