Michael Phelps just swam his way into the history books by winning more Olympic medals than anyone, ever. Pretty impressive, considering that the same guy was publicly shamed and persecuted just a couple short years ago for choosing to relax with a substance that is demonstrably safer than alcohol. But should we really be surprised? We’ve all seen the negative effects that alcohol can have on athletic training and performance. And after all, a recent study showed that marijuana has no long-term negative…