[Studies on the influence of various mathematical formulations on the determination of the proportion of fat in relation to bodyweight by means of skin fold measurements (author's transl)].

The paper reports on investigations on the influence of various mathematical formulations on the determination of the proportion of fat in relation to body-weight by means of skin fold measurements. For this purpose, the various equations derived from Archimedes' law, as well as the densities of various body fractions as determined by different authors, are discussed. This is followed by a discussion of the deliberations on the methods to be employed for estimating the density of the body by means of skin fold measurements. The various formulations differ from each other mainly by the location and number of measuring points. It was shown by means of comparative studies that for children aged between 9 and 16, independent of their sex, it will be sufficient to employ two skin folds (triceps and scapula). The existence of a very close correlation between the measured data of these points of measurement was found when using different calipers and the relevant conversion factors. In this manner it becomes possible to use a nomogram which has already been determined by Parízková and which was converted into a matrix for easier calculation. The determination of the relative proportion of fat'via skin fold measurements cannot replace the determination of individual body density by weighing under water. However, in mass examinations it is very well suited for differentiating between various groups of children (e.g. overweight, underweight, trained, and untrained) in respect of their relative proportion of fat.