The thing with the swimming is that it is sensory terrific for him because of the water enveloping all those nerves and the buoyancy and all the bazillion muscles that you use. And socially it is terrific because he has tons of friends yet other than a few relay teams it is an individual sport (so no one is counting on him to say hit a home run or catch a forward pass or something). And all the bilateral movement is good for him. Also, the workouts are very strenuous/aerobic. Baseball practice has a good warm up but really how much are you really exercising standing out in left field or sitting on the bench waiting to bat. Finally, he is very talkative and during laps he is quiet with his own thoughts. One time he told me during cool down he outlined his next great novel.
