单选题
Walking to Exercise the Brain

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!

单选题 Walking regularly helps elderly people______.
【正确答案】 C
【答案解析】[解析] 原文是第2段“对老年人的新研究显示经常运动能让他们更集中精力”。A:减肥;B:更愉快;C:精力更集中;D:显得年轻。因此只能选C。
单选题 After taking exercise for a few weeks, the mice were found to have______.
【正确答案】 C
【答案解析】[解析] 原文是第3段“以前的研究证明老鼠在轮子上奔跑数周后,它们的学习、记忆和集中程度都有所提高。运动的老鼠大脑中的血-液流量大于不运动的,而它们脑细胞的联系也更频繁。”A:更高的血压;B:更快的心跳;c:有更多血液流经大脑;D:更好的外表。因此只能选C。
单选题 The first study on 41 elderly people found______.
【正确答案】 B
【答案解析】[解析] 原文是第5段“研究员发现身体健康的成年人完成箭头测试的速度更快,他们的答案和身体状况不佳的参加者一样准确。”A:身体状况不佳的参赛者完成箭头测试更快;B:身体健康的参赛者完成箭头测试的速度更快;c:身体状况不佳的参赛者在箭头测试中答案更准确;D:身体健康的参赛者在箭头测试中答案更准确。因此只能选B。
单选题 It can be good for health when one takes a walk every 2 or 3 days for at least______.
【正确答案】 D
【答案解析】[解析] 原文是第7段“因此每两到三天仅仅出去散步10到45分钟都会对健康有益。”因此只能选D。
单选题 It is suggested in the last paragraph that people should______.
【正确答案】 B
【答案解析】[解析] 原文是最后一段“不管你怎么做都不要一边走路一边读书,你有可能伤到自己的”。A:一周跑一次步;B:不要同时走路和读书;C:每天散步;D:运动时不要伤着朋友。因此答案选B。