Marijuana vs. Sports

As we all know, Marijuana is illegal for athletes to use. But... If it was to become legal, do you think athletes would become more finesse and supernatural or would marijuana destroy athletes?

I've posted a pic below of 14 Gold Medal Swimmer and 16 overall medals, Micheal Phelps. The most anybody has in history. But wait... When you swim, you actually have to hold your breathe and move which takes a lot of lung capacity. But not only was he smoking weed... He smoking out of a BONG! GO MICHAEL PHELPS!!!