I did for many years while growing up and into my early 20's to stay around fighting weight, but after so long of it you get annoyed trying to stay on a strict diet. When I realized I didn't have the chin to ever fight pro and after I blew out my acl, I quit doing it. As long as you do exorcise, and by exorcise I mean at least a half hour a day of mild cardio at least, you can still enjoy big portions of good food and have some beers and stay in shape. I know how bad people hate running and I am surely one of them, advice to that is grab an elliptical machine of craigslist, it's a better full body cardio session than using a treadmill and for people with bad knees it takes away the impact.