I'm sure there are people who know more about this then I do, but I'll offer a quickie response.
1) This is the first time you've ever worked out. Unless you take steroids, you will never see such a fast increase in muscle mass. These athletes have been working out for a long time. It's not easy to put on mass after your "first cycle."
2) Also, you may have an ideal frame for putting on muscle mass. Do you have wide shoulders? Some men just have body types that make adding weight very hard to do.
Just a quick response.
__________________
|