# Hydrostatic weighing

## Description

Hydrostatic weighing, also referred to as “underwater weighing,” “hydrostatic body composition analysis,” and “hydrodensitometry,” is a technique for measuring the mass per unit volume of a patient’s body.The procedure is based on Archimedes’ principle, using the weight of the body outside the water, the weight of the completely immersed body (a weight that may be negative if the body in question is less dense than water) and the density of the water.

Related formulas## Variables

d_{b} | Density of the body (kg/m^{3}) |

d_{w} | Density of the water (kg/m^{3}) |

w_{b} | Weight of the body (kg) |

w_{im} | Weight of the immersed body (kg) |