Part B
Directions:
Read the following text and match each of the numbered items in the left column to its corresponding information in the right column. There are two extra choices in the right column. Mark your answers on the ANSWER SHEET. (10 points)
A busy brain can mean a hungry body. We often seek food after focused mental activity, like preparing for an exam or poring over spreadsheets. Researchers speculate that heavy bouts of thinking drain energy from the brain, whose capacity to store fuel is very limited. So the brain, sensing that it may soon require more calories to keep going, apparently stimulates bodily hunger, and even though there has been little in the way of physical movement or caloric expenditure, we eat. This process may partly account for the weight gain so commonly seen in college students.
Scientists at the University of Alabama at Birmingham and another institution recently experimented with exercise to counter such post-study food binges. Gary Hunter, an exercise physiologist at U.A.B., oversaw the study, which was published this month in the journal Medicine & Science in Sports & Exercise. Hunter notes that strenuous activity both increases the amount of blood sugar and lactate—a byproduct of intense muscle contractions—circulating in the blood and augments blood flow to the head. Because the brain uses sugar and lactate as fuel, researchers wondered if the increased flow of fuel-rich blood during exercise could feed an exhausted brain and reduce the urge to overeat.
Thirty-eight healthy college students were invited to U.A.B.’s exercise lab to determine their fitness and metabolic rates—and to report what their favorite pizza was. Afterward, they sat quietly for 35 minutes before being given as much of their favorite pizza as they wanted, which established a baseline measure of self-indulgence. At a later date, the volunteers returned and spent 20 minutes tackling selections from college and graduate-school entrance exams. Hunter says this work has been used in other studies “to induce mental fatigue and hunger.” Next, half the students sat quietly for 15 minutes, before being given pizza. The rest of the volunteers spent those 15 minutes doing intervals on a treadmill: two minutes of hard running followed by about one minute of walking, repeated five times. This is the sort of brief but intensive routine, Hunter says, that should prompt the release of sugar and lactate into the bloodstream. These students were then allowed to gorge on pizza, too. But by and large, they did not overeat. In fact, the researchers calculated that the exercisers consumed about 25 fewer calories than they did during their baseline session. The non-exercisers, however, consumed about 100 calories more. When the researchers factored in the calories expended on running, they determined that those students actually consumed 200 fewer total calories after their brain workouts than the resting students.
The study has limitations, of course. “We only looked at lunch,” Hunter says; the researchers do not know if the runners consumed extra calories at dinner. They also cannot tell whether other types of exercise would have the same effect as running, although Hunter says they suspect that if an activity causes someone to break into a sweat, it should also increase blood sugar and lactate, feed- ing the brain and weakening hunger’s call.
Researchers think that ________.
全文总体分析
文章分为四段,结构较为清晰。第一段指出为什么大脑忙起来人容易感到饿。第二段指出阿拉巴马大学伯明翰分校的科学家们和另一个研究机构试验通过运动对抗学习后的暴饮暴食。第三段说明实验的具体流程。第四段则指出了研究的局限性。
试题详解
根据题干关键词 Researchers 和 think 定位到第一段第三句 Researchers speculate that heavy bouts of thinking drain energy from the brain,其中 think 是 speculate 的同义替换;take the energy totally away from ... 是 drain energy from ... 的同义替换。 此句意为“研究者猜测,高强 度思考会耗尽脑部能量”,故本题选 C。
Hunter figures out that________.
根据题干关键词 Hunter 定位到第二段第三句 Hunter notes that strenuous activity both increases the amount of blood sugar and lactate, 其中 figure out 是对 note 的同义替换; tremendous是对strenuous的同义替换。 此句意为“亨特指出,剧烈活动会增加在血液中循环的 血糖和乳酸盐含量”,故本题选 E。
Blood sugar and lactate are produced by the fact that ________.
根据题干关键词 Blood sugar 和 lactate 定位到第二段第三句 Hunter notes that strenuous activity both increases the amount of blood sugar and lactate—a byproduct of intense muscle contractions,produce 意为“生产”,byproduct 意为“副产品”,两者虽词性不同,但其在意 义上相联系。 此句意为“亨特指出,剧烈活动会增加在血液中循环的血糖和乳酸盐含量———这是肌肉剧烈收缩的副作用”,故本题选 B。
The difference of consumed calories between exercisers and non-exercisers was that________.
根据题干关键词 exercisers 和 consumed 定位到第三段倒数第二、三句,即The non-exercisers, however, consumed about 100 calories more 和 In fact, the researchers calculated that the exercisers consumed about 25 fewer calories than they did during their baseline session, 将 倒数第二句中的 100 calories more 与倒数第三句中的 25 fewer calories 进行对比,可知做运动 者摄入的热量少于不做运动者所摄入的热量,故本题选 D。
The reason why the study has limitations is that________.
根据题干关键信息定位到第四段第三句 They also cannot tell whether other types of exercise would have the same effect as running,答案中的 are not sure 是对 cannot tell 的同 义替换,整句意为“他们也不知道其他类型的运动是否会收到和跑步一样的效果”,故本题选 G。
全文重点词汇和短语
spreadsheet n. 电子表格
speculate v. 投机;推测
stimulate v. 刺激
expenditure n. 开支;费用
account for 解释,说明
metabolic a. 新陈代谢的
baseline n. 基线;底线
self-indulgence n. 自我放纵
fatigue a. 疲劳的
treadmill n. 枯燥无味的工作
prompt v. 促进
gorge v. 狼吞虎咽
by and large 大体上
lactate n. 乳酸盐
weaken v. 削弱
全文翻译
大脑忙碌可能会导致身体饥饿。我们经常在集中进行脑力活动后寻找食物,比如备考或阅读报表。研究者猜测,高强度思考会耗尽脑部能量,而脑部存储养分的能力十分有限。所以,大脑感觉自己可能很快就需要更多热量来维持运转,显然会因此刺激身体产生饥饿感。尽管几乎没有进行体力运动或出现热量消耗,我们还是会吃东西。这个过程可以部分解释大学生中常见的体重增加现象。
前不久,阿拉巴马大学伯明翰分校的科学家们和另一个研究机构试验通过运动对抗学习后的暴饮暴食。这项研究由阿拉巴马大学伯明翰分校的运动生理学家加里•亨特主持,本月发表在《体育医学与科学》上。亨特指出,剧烈活动会增加在血液中循环的血糖和乳酸盐含量———这是肌肉剧烈收缩的副作用———增加脑部的血流量。大脑以糖和乳酸盐为养料,所以研究者们想知道,锻炼中增加的养料丰富的血流量是否能给疲惫的大脑提供养分,从而减轻过度进食的冲动。
38名健康的大学生被邀请到阿拉巴马大学伯明翰分校的运动实验室,接受健康水平和代谢率检测,并报告自己最喜欢吃哪种比萨。之后,他们静坐35分钟,然后他们想吃多少比萨就供应多少,以确定自我放纵的基线。在后来的一个日子里,志愿者们返回这里,花费20分钟时间做从大学和研究生入学考试中挑选的题目。亨特说,这种方法已经在其他研究中被用于“引发精神疲劳和饥饿感”。接下来,其中一半学生静坐15分钟,然后进食比萨。剩下的志愿者用15分钟时间在跑步机上做运动:快跑2分钟,然后走大约1分钟,重复5次。亨特说,这种短暂而高强度的运动应该能促使糖和乳酸盐释放到血流中。这些学生之后也被允许尽情食用比萨。总体来说,他们没有过量进食。实际上,研究者们计算出,这些锻炼者摄入的热量比在基线测试阶段大约少25卡路里。但是,那些没有锻炼的人大约多摄入了100卡路里。研究者们把跑步中耗费的热量计算在内后发现,那些学生实际上在脑力活动后比其他学生一共少摄入200卡路里。这项研究当然具有局限性。“我们只研究了午餐,”亨特说。研究者不知道跑步者在晚餐时
是否摄入了更多热量。他们也不知道其他类型的运动是否会收到和跑步一样的效果,不过亨特说,他们猜测,如果一项运动能让人出汗,那么它应该也能增加血糖和乳酸盐释放,给大脑提供养分,从而缓解饥饿感。