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{{B}} How Exercise Makes You Smarter{{/B}}
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(痴呆症).
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. 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 started an experiment. 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-up
A. steadily and more effectively
B. faster and more efficiently
C. more powerfully
D. more effectively