The aim: Of this study was to describe longitudinal changes in body composition and serum leptin, ghrelin and adiponectin levels over 36-month period in prepubertal rhythmic gymnasts (RG) and their age-matched untrained controls (UC) entering into puberty.
Methods: 35 RG (mean age 8.0±0.6 years) and 33 UC (8.2±0.6 years) were followed at 12-month intervals for the next 3 years. Height, weight, pubertal stage, body composition by DXA and serum leptin, ghrelin and adiponectin levels were measured at each time points.
Results: The pubertal development over the next 36 months was slower in the RC group where only 4 out of 35 girls reached Ma 3 whereas in the UC there were 14 girls at Ma 3. At 36 month RC had significantly higher serum adiponectin levels than UC (12.9±5.8 vs 9.8±4.4 μcg/ml; P<0.05). Serum leptin concentration per fat mass reached peak at 24 months in both groups being significantly lower in RC than in UC (0.52±0.2 vs 0.7±0.25 ng/ml per kg; P<0.05). Thus, relative leptin deficiency may be the reason for delayed pubertal development in RC. Serum ghrelin levels were highest at the beginning of the study, after that it started to decline reaching the nadir at 36 months in RC and at 12 months in UC. In RC baseline leptin concentration was negatively correlated to the change in body fat % over study period (r=−0.34; P<0.05). Change in BMI was negatively correlated with the change in serum adiponectin levels over the study period (r=−0.43; P<0.05).
Conclusions: The pubertal development in girls active in high-intensity rhythmic gymnastics is slower than in untrained girls. RC girls have relative leptin deficiency per their body fat mass. We speculate that relatively high serum leptin concentration at the beginning of puberty may predict those girls who do not increase their body fat % through coming years and therefore may have increased risk for delayed puberty. Further studies are necessary to confirm or reject our hypothesis.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology