Exercise does more than build muscles and help prevent heart
disease. New science shows that it also boosts brainpower—and
may offer hope in the battle against Alzheimer’s. The stereotype
of the “dumb jock” has never sounded right to Charles Hillman. A
jock himself, he plays hockey four times a week, but when he
isn’t body-checking his opponents on the ice, he’s giving his
mind a comparable workout in his neuroscience and kinesiology
lab at the University of Illinois. Nearly every semester in his
classroom, he says, students on the women’s cross-country team
set the curve on his exams. So recently he started wondering if
there was a vital and overlooked link between brawn and
brains—if long hours at the gym could somehow build up not just
muscles, but minds. With colleagues, he rounded up 259 Illinois
third and fifth graders, measured their body-mass index and put
them through classic PE routines: the “sit-and-reach,” a brisk
run and timed push-ups and sit-ups. Then he checked their
physical abilities against