I'm 20 and 5'10" and weigh about 180 pounds. I too am in really good physical shape (i played college baseball). I would stay away from anything like creatine or andro if I were you. Don't need it. I used something called an 'animal pak' which you can buy at gnc. Its packages of 10 or so pills that you take before you lift. Sure a few of them are horse pills, and they turn your urine like neon yellow, they are effective. They are simply vitamins and amino acids. I asked my friend's mom, who is an rn about them, and she said they should'nt be harmful at all.

Hope this helps

tee