Hormonal (cortical-gonadotropic axis) and physical changes with two years intense exercise training in elite young soccer players - Hammami, M. A.; Ben Abderrahman, A.; Hackney, A. C.; Kebsi, W.; Owen, A. L.; Nebigh, A.; Racil, G.; Tabka, Z.; Zouhal, H. (The Journal of Strength and Conditioning Research, 2017)