Summary

Abstract

Body composition, i.e. the relative and absolute amount of lean body mass (LBM) and depot fat is one of the most variable morphological characteristics of the organism. It is differentiated according to sex from the earliest periods of ontogeny, and undergoes changes throughout life not only in relation to growth, development and ageing, but above all in relation to caloric balance and energy turnover in the organism per unit of time. This depends mainly on nutrition and physical activity (i.e. muscle work). The growing organism has a relatively high calorie input in relation to body weight, and also a high basal and total energy output, which is, inter alia, mainly due to increased spontaneous physical activity in this period. The reverse applies to the ageing and old organism.