I'm interested in putting on some pounds of muscle. I'm currently 16, 5'10, and about 142 pounds. I wanna just get to about 150 and I think that should be enough. I am doing p90x right now but I cant really follow the nutrition guide as there are a bunch of things on there that I do not have in my house. However, I do like to eat a lot of protein and after each workout, I take an isopure shake (0 carbs, 50g of protein). My problem is that I am in the 4th week of p90x and I've been killing myself and I haven't really had a change in weight. I'm pretty ok and I would say I am under 10% body fat because I can see my upper abs and a little bit of my lower abs. I just want to gain some good muscle and I think now is the best time to do it because I do not play as much tennis. I know everyone says that it takes a long time but my p90x program finishes on March 28th and I want to be about 150 lbs by then... Can anyone help me out?