ABSTRACT
Height, body mass and BMI increased accordingly to the pubertal development in all boys at each measurement point. Peak oxygen uptake was increased and ghrelin concentration was decreased only after the first year of measurement. Ghrelin concentration was significantly related to BMI at all three measurement times (r=-0.551 to -0.661) and 2 peak (r=-0.482 to -0.503). 13.4 CONCLUSIONS Circulating ghrelin levels remained relatively high also during puberty in our young swimmers compared to other studies with untrained boys (Whatmore et al., 2003). In our previous study physically active girls (swimmers) had significantly higher mean plasma ghrelin levels than physically inactive girls (Jürimäe et al., 2007). In our study fasting ghrelin was not correlated significantly with Tanner stages. Bellone et al. (2002) concluded that ghrelin was independent of pubertal status in lean children. This means that our results support the possibility that ghrelin may act independently during different stages of maturation in the presence of regular high energy expenditure in swimmers. In conclusion, the ghrelin concentration was decreased and peak oxygen consumption increased at onset of puberty, while no further changes were seen with advancing age and pubertal stage in young male swimmers. Finally, ghrelin concentration in blood correlated negatively with peak oxygen consumption. 13.5 REFERENCES Bellone, S., Rapa, A., Vivenza, D., Castellino, N., Petri, A., Bellone, J., Me, E.,
Broglio, F., Prodam, F., Ghigo, E. and Bona, G., 2002, Circulating ghrelin levels as function of gender, pubertal status and adiposity in childhood. Journal of Endocrinological Investigation, 25, pp. RC13-RC15.
