Abstract des Autors

Relationships between body height/weight proportions and the age at menarche were determined in 13565 girls aged 10 to 18 years, studied in the years 1986-89 for establishing the the socioeconomic stratification of the rural population. The girls were grouped in half-year intervals and subdivided in three classes - medium (mean +/- 0.5 SD), low, and high, regarding body mass, body height, and body robustness. For each subgroup the age at menarche was determined by the probit method. Also, body mass, height and robustness were computed for girls of the same chronological age but differing in having had or not yet menarche: menstruating girls aged 13.5 years were heavier (by 8.1 kg), taller (by 4.3 cm) and more robust (by 1.3 units of the ponderal index) from their non-menstruating mates. In order age groups those differences were generally higher. Further, in each age group 7 classes of robustness were discerned. Girls of a slendermost build had menarche by 1.8 years later than their most robust mates. The results show that the adolescence rate is an important factor to be considered when selecting girls for competitive sports. Moreover, the fact that young athletes are late maturing, is the result of preferring slim girls to engage in competitive sports. Verf.-Referat