VALIDITY OF BIOELECTRICAL IMPEDANCE ANALYSIS COMPARED TO HYDROSTATIC WEIGHING IN MEASURING BODY COMPOSITION OF MIDDLE- AGED WOMEN

Bennis EA, Fatheree BJ, Mesang JN, Palmer DJ, Tauscheck EL. Validity of Bioelectrical Impedance Analysis compared to Hydrostatic Weighing in Measuring Body Composistion of MiddleAged Women. Journal of Undergraduate Kinesiology Research 2006;2(1):41-48. Purpose: Two current methods for assessing total percent body fat among individuals are the Tanita Bioelectrical Impedance Analysis (BIA) device and hydrostatic underwater weighing. The purpose of this study was to determine the validity of the Tanita Bioelectrical Impedance Analysis device when compared with Hydrostatic Weighing in measuring body composition among women ages 18 to 45. Methods: We recruited13 between the ages of 18 and 45 from the Eau Claire, Chippewa Valley area for our study. The subjects were of various physical activity levels ranging from inactive to highly active; however, highly trained women, those who participated in two or more high intensity exercise sessions per week, were excluded form the study. After being introduced to the testing procedures, subjects were measured using the Tanita Bioelectrical Impedance device and hydrostatic weighing to determine their percent body fat. After hydrostatic weighing, subject’s residual lung volume was measured using the EXERTECH RV system in order to calculate percent body fat. All subjects underwent multiple trials of hydrostatic weighing and Tanita BIA measurements in order to ensure validity. All measurements procedures were conducted on the same day for each subject. This study compares the validity of the Tanita Bioelectrical Impedance Analysis device to hydrostatic weighing using a sample t-test. Results: The results of our study show that there is a significant difference between body fat percent as determined by the Tanita BIA device and hydrostatic weighing among women between the ages of 18 and 45. Conclusion: Results are important because BIA devices are becoming more popular and widely used. It is essential for health and fitness professionals to realize results from this tool should not be considered valid.