新視野大學(xué)英語讀寫教程第三冊(cè)u(píng)nit2-b Does Exercise Have Unexpected Benefits

Section (B)

Does Exercise Have Unexpected Benefits?

Just as exercise strengthens the heart and lungs, bones and muscles, it may also power up the brain. A succession of scientific studies of animals implies that physical activity has a positive effect on mental functioning. "It's clear that the brain benefits from exercise," says brain scientist William Greenough of the University of Illinois at Urbana-Champaign. His studies with rats have demonstrated two primary effects of activity: vigorous physical exercise provides the brain with more fuel, and skill-based exercise

increases the formation of connections in the brain, which, according to the proposals of some scientists, may make the brain better able to process information. In one experiment, laboratory rats were separated into three groups. One group was exercised by running inside an automatic wheel, a second group improved their skills in a complicated obstacle course, and a third group was inactive.

"The animals that learned to go through the obstacle course exhibited a greater number of brain connections than the animals in the exercised or inactive groups," Greenough said. "In contrast, the animals that exercised inside the automatic wheel possessed a greater density of blood vessels in the brain than did either of the other two groups of animals." Learning a new dance step may boost the brain in the same way that learning a language can, he says. And if the dance is a good physical exercise as well, the benefits multiply. Young brains may be especially able to boost brain power through exercise, suggested another of Greenough's experiments that showed the most significant changes in the brain occurred among rats that had been exercised when very young. And while animals aren't people, he says it is logical to make the inference that an effect found in rats may also apply to humans.

Human studies have focused primarily on older adults and suggest that regular exercise can improve the speed with which the brain processes information. Measurements made by Arthur Kramer at the University of Illinois demonstrated that inactive adults, aged 63 to 82, could hit buttons faster in response to a tone after they went through a 10-week water exercise course. A corresponding control group that didn't exercise showed no improvement. This boost in reaction time after exercise training may occur because declines associated with getting old could actually stem from declines in physical condition. Some scientists speculate the reduction in mental function often attributed to getting old may really be a penalty of neglecting to stay physically active, in addition to related factors such as medicines and poor diet. "In older people, an exercise program appears important for brain maintenance," says Daniel M.

Landers, professor of exercise science at Arizona State University, who recently published an article reviewing the scientific literature on activity's effect on the brain.
Numerous studies show that children who engage in regular physical activity do better in school than their inactive classmates. But until recently, the academic edge gained by participating in sports was thought to come from the increased self-confidence, the better mood, and the ability to concentrate that comes from burning off steam in exercise. Now, however, some scientists have revised their way of thinking, and point to possible physical connections.

Pierce J. Howard, another expert, says new research indicates that physical exercise increases the amount of certain brain chemicals that stimulate growth of nerve cells. Consequently, the brains of people who exercise may be better equipped to tackle mental challenges. Inactivity may also have negative effects on mind and body alike. "Scientists recognize that mind is body, and body is mind," comments Howard. The most beneficial forms of exercise, he says, engage both.

Words: 602

New Words

　succession n. 1.一連串的事物，一系列 2.連續(xù)，接續(xù) 3.繼任(權(quán))，繼承(權(quán))
　imply vt. 暗示，暗指
　rat n. 鼠，大老鼠
　primary a. 1.首要的，基本的，主要的 2.最初的，最早的
　vigorous a. 強(qiáng)壯的，有力的，精力充沛的
　formation n. 1.組成，形成 2.形成物，結(jié)構(gòu) 3.排列，隊(duì)形
　proposal n. 1.建議，計(jì)劃，方案 2.求婚
　laboratory n. 實(shí)驗(yàn)室
　complicated a. 復(fù)雜的，難以理解或解釋的
　obstacle n. 障礙（物）
　exhibit vt. 1.顯示，顯出 2.陳列，展覽 n. 展覽品，陳列品
　possess vt. 擁有，具有
　density n. 密集；密度
　multiply v. 1.（使）增加，（使）繁殖 2.乘
　boost vt. 改善，提高，增強(qiáng)，推動(dòng) n. 增加；幫助；鼓舞
　logical a. 合乎邏輯的，條理分明的
　inference n. 1.推斷的結(jié)果，結(jié)論 2.推論，推斷，推知
　primarily ad. 首先，主要地，基本地
　measurement n. 1.測(cè)量，衡量 2.（量得的）尺寸，大小
　corresponding a. 相應(yīng)的，對(duì)應(yīng)的
　stem vi. 源于，由... ...造成 n. （植物、灌木或樹木的）莖，干
　speculate v. 推測(cè)，推斷
　reduction n. 1.減少，減低，減縮 2.減少，減低，縮小
　penalty n. 處罰，懲罰；罰金
　neglect vt. 1.忽視，忽略 2.遺忘 n. 疏忽，忽略
　maintenance n. 1.維護(hù)，保養(yǎng) 2.保持，維持
　academic a. 1.學(xué)術(shù)的，學(xué)院的 2.純理論的，不切實(shí)際的
　concentrate v. 1.集中，集中精神 2.集中，聚集
　revise vt. 1.修正，修改 2.復(fù)習(xí)，溫習(xí)
　cell n. 細(xì)胞
　consequently ad. 因此，所以
　equip vt. 1.使有準(zhǔn)備 2.配備，裝備
　tackle vt. 1.處理，應(yīng)付 2.與... ...交涉
　alike ad. 一樣地，相似地 a. 相同的，相像的
　comment v. 評(píng)論，發(fā)表意見 n. 評(píng)論，意見
　beneficial a. 有助的，有利的，有益的

Phrases and Expressions

　separate… into 將... ...分為
　obstacle course 越障訓(xùn)練；（喻）困難重重的事
　go through 完成，通過
　in contrast 相比之下
　apply to 適用于
　focus on 集中于
　engage (oneself) in 從事，忙于
　point to 表明；表示

Proper Names

　William Greenough 威廉·格里諾
　University of Illinois at Urbana-Champaign 伊利諾伊大學(xué)厄巴納-尚佩恩分校
　Arthur Kramer 阿瑟·克雷默
　Daniel M. Landers 丹尼爾·M. 蘭德斯
　Arizona State University 亞利桑那州立大學(xué)
　Pierce J. Howard 皮爾斯·J. 霍華德