My niece asked (for "a friend's kid") and she was unsatisfied with "a lot, but it's not worth it because of risks and repercussions I can't name." I'm not pointing any fingers, but I got tall the old fashion way. This seems to be something not discussed in youth sport. I'm sure it effect football too. Since teens have such varying amounts of HGH, I doubt it could be detected or a specific level determined to be incriminating.