Validity and sensitivity measures of the BIA in response to overhydration

Abstract

Repeated body composition analyses were performed on 30 male volunteers aged 18-25 yrs. The Ss were measured both before and after hydration by hydrostatic weighing (HW) and bioelectrical impedance analysis (BIA). Validity measures of the BIA were examined relative to HW. Sensitivity of the BIA was measured in response to an overhydration volume of 1.5% of body weight in tap water. The validity of the BIA for % BF was found to be sig (p < 0.05) overestimated (2.6 - 3.1%). Neither the BIA nor HW were sensitive to overhydration as they were not found to be sig (p < 0.05) for % BF or LBM. Future studies could include larger fluid volumes and larger, more, homogenous sample in an effort to statistically emphasize the physiological effect of hydration and the BIA's potential ability to detect such changes.