COMPARISON OF BODY DENSITY VALUES WHEN HYDROSTATICALLY WEIGHED IN A SWIMMING POOL AND A TANK 335

Abstract

The purpose of this investigation was to compare body density values when hydrostatically weighed in a swimming pool and a tank. These values were also compared on the bases of two different methods of determining water density, temperature alone (TA) and direct weighing of water (DW). Additionally, an attempt was made to further verify water density values by eliminating human inconsistencies in the pool and tank. An inanimate object was underwater weighed to determine if any difference existed between the two sets of measurements. Twenty male students in the Movement Studies and Exercise Science program at East Stroudsburg University served as subjects in this investigation. Measures of body weight were obtained in a swimming pool and in a hydrostatic weighing tank. A total of ten underwater weights were obtained for each subject in each testing environment with the heaviest weight recorded as the true underwater weight. Means and standard deviations of body density in the pool (TA, 1.07008 ±.00950; DW, 1.07000 ±.01055) and tank(TA, 1.06808 ±.00856; DW, 1.06893 ±.00865) were calculated by temperature alone and direct weighing of water respectively. Also, means and standard deviations of water density in the pool (TA,.99615 ±.00036; DW,.99686 ±.00036) and tank (TA,.99579 ±.00032; DW,.99654±.00035) were calculated by the temperature alone and direct weighing of water methods. Difference between body density values and water density values in the pool and tank were tested using dependent t-tests (p<.01). The results indicated that water densities are different when measured from temperature alone or by direct weighing, and whether in the pool or tank. However, the degree to which differences in water density affected body density and ultimately body fat, was negligible.