Hydrostatic weighing or underwater weighing compares your normal body weight outside the water to your body weight while completely submerged in the water. Based on your buoyancy and your weight the person administering the test can calculate your body fat percentage. You measure skin flaps at various points on your body and use a mathematical formula to calculate body fat. Calculating body fat percentage isnt always completely accurate and there are many methods to try. These parts of our body contribute to our underwater weight uww by either helping us to sink or float and their densities are approximately as follows. Underwater weighing for body fat percentage is highly accurate and considered the gold standard for measuring body fat percentage.
Hydrostatic weighing also referred to as underwater weighing hydrostatic body composition analysis and hydrodensitometry is a technique for measuring the density of a living persons body. Hydrostatic underwater weighing or hydrostatic testing is a method of determining body composition body fat to lean mass. Fat floats density approximately 09 gcc muscles sinks 11 gcc and the air inside out lungs and gi tract floats 00012 gcc. It is a direct application of archimedes principle that an object displaces its own volume of water. Hydrostatic body fat testingservices hydrostatic body fat testing as body fat testing rather than simple scale weight has become the standard in this new millennium hydrostatic testing underwater weighing has become universally regarded by industry experts as the gold standard in body fat testing. Underwater testing is considered to be an accurate tool for measuring body fat.
It measures a persons total body density using archimedes principle of displacement. The percentage that it estimates should be within 1 percent of. Skinfold measurements have been used to estimate body fat for over 50 years skinfold calipers measure the thickness of your subcutaneous fat the fat underneath the skin at certain body. Water displacement provides a higher degree of accuracy plus or minus 15 percent but skin calipers provide greater convenience that may encourage more frequent assessments. Well talk about the healthy range for men and women and the limitations. Using these two numbers and the density of the water operators can accurately determine body volume and density along with the breakdown of fat mass vs.
1 hydrostatic underwater weighing has been considered the gold standard for body composition assessment.