Can exercise build bigger brains?

Can Exercise Make Kids Smarter? Several recent experiments link aerobic exercise with brain development, reports the New York Times.

In a University of Illinois experiment involving  nine- and 10-year-old students, the fittest children, as measured by a treadmill test, performed best on cognitive challenges; MRIs showed “significantly larger basal ganglia, a key part of the brain that aids in maintaining attention and executive control.”

Since both groups of children had similar socioeconomic backgrounds, body mass index and other variables, the researchers concluded that being fit had enlarged that portion of their brains.

A second Illinois study focused on complex memory, which is associated with activity in the hippocampus. The fittest children had larger hippocampi than the least-fit children.

A Swedish study of more than a million 18-year-old boys who joined the army, found “better fitness was correlated with higher I.Q.’s, even among identical twins,” the Times reports.

The fitter the twin, the higher his I.Q. The fittest of them were also more likely to go on to lucrative careers than the least fit . . . There’s no evidence that exercise leads to a higher I.Q., but the researchers suspect that aerobic exercise, not strength training, produces specific growth factors and proteins that stimulate the brain, said Georg Kuhn, a professor at the University of Gothenburg and the senior author of the study.

Aerobic endurance, not muscular strength, was linked to a livelier  brain.

According to a new UI study, not yet published, Wii Fit will not make us smart. Twenty  minutes of running on a treadmill improved test scores immediately afterward;  20 minutes of “playing sports-style video games at a similar intensity” did not.