What technique measures air displacement to estimate body volume?

Air Displacement Plethysmography is the correct technique for measuring air displacement to estimate body volume. This method operates on the principle of the relationship between pressure and volume, determining body composition by calculating how much air is displaced by a person's body in a sealed chamber.

When a person enters the chamber, the equipment measures the pressure changes that occur as the body occupies space within the enclosed environment. By comparing these measurements with values known for the chamber's volume without a person, this technique accurately estimates the body volume, which is essential for determining body density and composition.

In contrast, hydrostatic weighing involves submerging the individual in water to measure density based on water displacement. Bioelectrical Impedance Analysis uses electrical currents to estimate body composition based on resistance, and Dual X-ray Absorptiometry (DXA) utilizes low-level X-rays to differentiate between bone mass, lean mass, and fat mass. Each of these methods has its own principles and applications, but only Air Displacement Plethysmography specifically utilizes air displacement for volume estimation.