Somatic Development of Boys during the Prepubertal Period and at the Onset of Puberty

Overview

The age range of the prepubertal developmental period in boys is between the age of 6 and 7 years resp. andthe age of 12 (in girls between 6 and 10 years). The upper borderline of this interval displays, however,a considerable interindividual variability as regards the onset of puberty. Based on an analysis of 67 anthropomet-ric and functional parameters in a group of 763 healthy boys aged 7 to 13 years the author evaluated developmentalcorrelations and trends typical for the period of prepuberty and the onset of the pubertal growth acceleration. Itwas confirmed that prepuberty is the period of relative developmental quiescence when the development ofdifferent somatic parameters is slow and proportional. An exception is to a certain extent only height and signsassociated with it (length of the upper body segment, length of the lower extremity etc.) where at the age of cca 8years a mild growth acceleration was found described as mid-growth spurt. A typical phenomenon of prepubertyin boys is a change in the subcutaneous fat distribution from the peripheral type to the centripetal one. Thisphenomenon can be recorded already from the age of 7 years, the general change of this ratio can be reliablyconfirmed however only after the age of 15 years. At the onset of the pubertal growth acceleration which in boysis on average between the age of 12 and 14 years the dynamics of growth of different somatic parameters increaseagain markedly.

Key words:
prepuberty, onset of puberty, boys, somatic growth and development, body composition, distribu-