You know you should exercise regularly. You want to look good, feel good and be healthy. But now researchers are saying that exercise can also help increase your brainpower.

Neuroscientists at Columbia University found that when their subjects worked out for one hour, four times a week, they ended up pumping more blood to the part of their brain that controls neurogenesis--the creation of new brain cells--than the control group did. The part of the brain affected is also important for creating and processing memories--and predictably, the subjects who exercised did better on word-recall tests than the control group, too.

While this study was performed on subjects between the ages of 21 and 45, there have been similar studies on school-age children and the elderly that have produced the same kinds of results. It kind of makes you want to rethink the stereotype of the dumb jock.

So if you're looking for some motivation to get moving--or just want to see how your fitness routine stacks up against that of other entrepreneurs, check out our article, "The Pedometer Challenge," where we tracked four entrepreneurs for a week to find out how active they are compared to people with desk jobs.