I know @Tenacious E has sought advice for strength training for his teenage son. My son is 15 and about 5’10” and a buck 35ish. He is mainly a linebacker in football and infielder in baseball. He is looking to add some weight but has his old man’s genes. I have no problem with wanting to add weight, the question is, how do we do it safely without adding bad weight? I’m not worried about the strength and conditioning aspect, but what about supplements at his age? @ClarindaA's, @Monzon or anyone else with expertise care to share? @Herkmeister no offense, but you can sit this one out.