Is prepubertal growth adversely affected by sport?

Purpose: To study the effect of genetic factors, birth weight early childho od growth, sport, hours of training, and pubertal status on the stature and body mass index (BMI) of children aged 9-13 participating in sports at a c ompetitive level. Methods: A total of 184 children (96 girls, 88 boys), com peting in swimming, tennis, team handball, and gymnastics, were investigate d, assessing their height, weight, pubertal development, and BML. Of these, 137 (76 girls, 61 boys) returned a questionnaire, which enabled us to dete rmine height and BMI at age 2-4, birth weight, and parental heights. Result s: Significant differences in standard deviation scores (SDS) for actual he ight and for height at age 2-4 were found in both sexes between the four sp orts. In girls, BMI SDS was significantly different between the four sports , whereas no difference was found in boys. Each sport investigated separate ly showed no change in height SDS and BMI SDS between ages 2-4 and 9-13. A regression analysis showed that target height, height at age 2-4, and puber tal status had a significant impact on actual height. Interestingly, the ty pe of sport and hours of training per week had no effect on height SDS. In boys, BMI at age 2-4 and pubertal status had a significant effect on actual BMI, whereas in girls, only BMI at age 2-4 was significant. Conclusions: T he results suggest that prepubertal growth is not adversely affected by spo rt at a competitive level and that constitutional factors are of importance for choice of sport in children.