Some guys I train with suggested ZMA (Zinc Monomethionine Aspartate) to take strength training to the next level. I am a 20 year old male so I don't want anything screwing with my growth hormones, etc; but apparently this stuff is supposed to be a safe supplement that naturally increases testosterone levels to improve muscle gains. Any thoughts on this? I want to hear someones take on this that obviously knows more about it than me. Also, any good suggestions for safe supplements to help with my strength on the mat?