Don't Forget
You Still Need...
Of course, you still need a good source of protein. The roll of IGF-1 and testosterone is to make muscle out of it so you need the building blocks. If you're going to buy protein powder, best to get a hydrolized whey product...much easier for an older stomach to digest. Just try to stay away from artificial sweetners.
Also daily vitamins. They're all important. Do your
research and get some good ones.
Creatine? Sure. Get some. Just no need to take the astronomical amounts the mfgs want you to take.
Adequate sleep. 6-8 hours.
Get some regular cardio in there too.