Which method uses buoyancy to determine body composition?

Hydrostatic weighing is a method that utilizes buoyancy to assess body composition by measuring an individual's weight in and out of water. This technique operates under the principle of Archimedes' principle, which states that an object submerged in fluid experiences a buoyant force equal to the weight of the fluid displaced.

In hydrostatic weighing, the individual is weighed on land and then submerged in water. The difference in weight allows for calculations to determine the density of the body. From this density, body fat percentage can be estimated because fat and lean mass have different densities. This method is considered one of the most accurate ways to measure body composition and is often used as a reference standard in research and clinical settings.

Other methods listed, such as skinfold measurements, DXA scans, and bioelectrical impedance analysis, utilize different mechanisms, such as measuring skinfold thickness, assessing bone mineral density and body fat using X-ray technology, and passing a small electrical current through the body, respectively. These techniques do not rely on buoyancy or underwater weighing to evaluate body composition.