Exercise builds small blood vessels in brain, study says

study reflects correlation, not causation,
ie. maybe people who exercise are more likely to eat veggies, and veggies are the cause of small blood vessel propogation, etc.
perhaps use mouse model to confirm

Studies have shown that exercise does people smarter and more alert, even young people. Some of these studies have been conducted in Japan.

It is kind of obvious, more blood flow to the brain equals more nutrients, oxygen, etc, which will result in better performance. Obviously that does not mean that is the only factor. Mathematicians and physicists probably are smarter than professional athletes (probably), however I know mathematicians and physicists that do regular exercise, and they seem more intelligent than their peers (I don't have formal proof of it...)

excercise also strengthens other internal organs so its multi benefit in anycase for the body