The contribution presents an analysis of anthropometric parameters necessary for the determination of biological - proportionality age, as well as analysis of the given index. The state of the applied criteria has been verified after 19 years, 1046 boys and 1604 girls being examined. The proportionality of the children have not changed, the boys displayed also identical values of KEI, the higher difference of 0.02 units in favor of 13-years old subjects being observed. The situation in girls was similar, while the higher increase of the index was observed in the 10 years old subjects (0.02 units). The comparison of body height with the condition 19 years ago (CZ Spartakiad national gymnastics festival) gives evidence of a manifestation of deceleration in the children age period, with an indication of a secular tendency at the juvenile age (15 and 16 years). The development of the mean values of body mass suggests a certain stability of this index for the whole developmental growth period. There is a fluctuation of body height in girls, again with the manifestation of a secular tendency in juvenile age categories. The lower mean body mass in present girls is more apparent than in boys, but it seems impossible to declare a fluent tendency of getting slimmer. The prevailing somatic types with predominant endomorphism should be given more attention especially in view of latent obesity. The study was elaborated within the framework of fulfilling the grant project GA CR 406/02/0146.

        Key words: biological age, proportionality age, normative data, age 6 - 17 years