While you could just make San Andreas ' home boy CJ eat himself stupid and balloon up to E. Honda proportions, there's also unarguable stat boosting that comes from putting the hours in at the gym. If you can do it in the game and see results, why not do it in real life? The game is teaching you that a "little and often" approach to exercise will let you climb walls better, run for longer without getting puffed out and increase your sex appeal. So step away from the pie and chips and do as CJ does. Well, not everything CJ does, obviously.
Above: That gangster's wearing a kerchief because CJ stinks. Do you want to look like this?