Discrepancy in IGF-1 and GH response to submaximal exercise in young male subjects l'exercice submaximal chez des sujets jeunes

Objective: To examine the hormonal changements of the GH-IGF axis in response to submaximal exercise in young male subjects. Material and methods: The study involved a group of 13 male volunteers aged 15.83+/-0.63 years. They took part in a moderate-intensity exercise which consists on 15 minutes of running. Venous blood samples were collected immediately before the exercise (t0), at the end (t15) and after 45 min of recovery (t60). Serum levels of GH, IGF-1, IGFBP-3 and insulin were measured in each of the samples. Results: The main finding of our study is that we have proved the hypothesis that any acute increase in circulating IGF-1 in response to exercise is GH-independent, because IGF-1 increases after exercise (P