d**k Cheney has a little story on visualizing golf when eh was held captive before to stimulate the mind when he couldnt exercise or anything, so he wouldnt get psychological deterioation.
And form what science I know, golf, tennis, and ping pong are the best sports for the mind, they acheive the highest brainwaves (their athletes) out of any other sport.
Plus, theres a type of meditaiton which has similar brainwave levels.
Plus, there were studies on visualizing techniques, in russia for instance, they found of three groups the ones who visualized the most improved the most
it was like 3/4 exercise, 1/2 exercise, or 1/4 exercise, with the rest being visualization.
The ones who visualzied the most did best.
But socializaiton is very important for the mind too.