单选题 Do you think sitting and studying all the time will improve your grades? Think again. Getting some exercise may help, too.
New research with older people suggests that taking regular walks helps them pay attention better than if they didn"t exercise.
Previous research had shown that mice learn, remember, and pay attention better after a few weeks of working out on a running wheel. Mice that exercise have greater blood flow to the brain than those who don"t. Their brain cells also make more connections.
Neuroscientists from the University at Urbana-Champaign wanted to find out if the same thing is true for people. First, they measured the physical fitness of 41 adults, ages 58 to 77, after each person walked 1 mile. Then, participants looked at arrows on a computer screen and had to use computer keys to show which way one particular arrow was pointing.
Adults who were physically fit were faster at the arrow task, and their answers were just as accurate as their less-fit peers, the researchers found. The fitter participants also had more blood flow to a part of their brain responsible for paying attention and making decisions.
In a second study, 15 elderly people who completed a 6-month aerobic-training course were faster at attention tasks compared with 14 seniors who just did stretching and toning exercises for the same amount of time.
So, even going for a walk every 2 or 3 days for just 10 to 45 minutes can help. That should be good news for your grandparents.
The effects of exercising on the brains of younger people haven"t been studied yet. Still, it can"t hurt to take occasional study breaks and go for a walk or run around with your friends. You might even do better in school.
Whatever you do, though, don"t try to read and walk at the same time. You could end up hurting yourself!

【正确答案】 C

【答案解析】[解析] 细节题。利用regular walking可以定位到第二段“New research with older people suggests that taking regular walks helps them pay attention better than if they didn"t exercise”，意为“对老年人的新研究显示经常运动能让老年人更集中精力”，因此答案为C“更好地集中精神”。