The actual problem of body composition (BC) evoked the formulation of five models of BC and development of evaluating methods. Currently used methods are principally based on measured values of indicators (body density, total body water), which are later on converted into parameters identifying BC.In hydrodensitometry we use a water tank (90x110x145 cm) above which there is a weighing chair assembly and mobile scales with an accuracy of 0.001kg.
The measured person is weighed on land at first, than under water after maximal expiration.The result of underwater weighing is 10 values of weights under water, of body densities and of fat percentage according to various prediction formulas in every tested person.Limitations of hydrodensitometry consist of an individual fluctuation of hydration of fat free mass and of density of particular components related to age, sex and amount of fat mass.