共用题干 第一篇 Walking to Exercise the Brain Do you think sitting and studying all the time will improve your grades?Think again.Getting some exer- cise may help,too. New research with old 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（神经科学家）from the University of Illinois 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（有氧运动）course were faster at attention tasks compared with 14 seniors who just did stretching and toning exercises（韵律操）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 the elderly. The effects of exercising on the brains of younger people haven't been studied yet. Still,it can't hurt to take occasional breaks and go for a walk or run around with friends.Whatever you do,though,don't try to read and walk at the same time.You could end up hurting yourself! The first study on 41 elderly people found______________. A:the less-fit participants did arrow tasks faster B:the fitter participants did arrow tasks faster C:the less-fit participants gave more accurate answers D:the fitter participants gave more accurate answers
