Drinking eight cups or two litres of water a day is longstanding advice. But is
题型：不详难度：来源：
Drinking eight cups or two litres of water a day is longstanding advice. But is there any scientific basis for it, asks Dr Chris van Tulleken.
You know those ads that remind us that even a small drop in hydration（水合作用） levels can massively affect performance so you need to keep hydrated with whatever brand of super drink they"re selling?
They seem pretty scientific don"t they? Man in white coat, athlete with electrodes attached and so on. And it"s not a hard sell because drinking feels right - you"re hot and sweating so surely replacing that fluid must be beneficial.
Well earlier this year sports scientists in Australia did an extraordinary experiment that had never been done before.This group wanted to find out what happened to performance after dehydration. So they took a group of cyclists and exercised them until they lost 3% of their total body weight in sweat.
Then their performance was assessed after rehydration with either 1) nothing, 2) enough water to bring them back to 2% dehydration or 3) after full rehydration.
So far nothing unusual, but the difference between this and almost every other study that"s ever been done on hydration was that the cyclists were blind to how much water they got. The fluid was given intravenously without them knowing the volume.
This is vital because we all, and especially athletes, have such an intimate(密切的)psychological relationship with water consumption.
Remarkably, there was no performance difference between those that were fully rehydrated and those that got nothing. This study was part of a growing movement to "drink to thirst" which hopes to persuade athletes not to over hydrate with the potentially fatal consequence of diluting your sodium level, causing hyponatraemia.
Perhaps the result shouldn"t be so surprising. Humans evolved doing intense exercise in extreme heat and dryness. We are able to tolerate losses in water relatively well whereas even slight over hydration can be far more dangerous. In simple terms, being too watery is as bad for you as being too concentrated.
小题1:What’s the main idea of the passage?| A．There is no scientific basis for drinking eight cups of water a day | | B．People used to drink eight cups of water a day | | C．An experiment about whether people should drink eight cups of water. | | D．People shouldn’t believe longstanding advice. |
小题2:what does the word“dehydration ”in paragragh 4 mean？| A．doing exercise | B．losing water | | C．drinking water | D．having a rest |
小题3:What is NOT TRUE according to the passage?| A．Drinking too much water is bad for us | | B．Sports scientists in Australia did an extraordinary experiment for the first time. | | C．Those that were fully rehydrated and those that got nothing performed differently. | | D．The cyclists didn’t know how much water they got. |
小题4:What can we learn from the last paragragh?| A．Humans can bear losing water relatively well | | B．It’s dangerous to drink water. | | C．Athletes should drink more water than others. | | D．This study was part of a growing movement to "drink to thirst". |
小题5:what is Dr Chris van Tulleken’s attitude towards the. longstanding advice？| A．positive | B．doubtful | C．supportive | D．indifferent |
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答案
小题1:A
小题2:B
小题3:C
小题4:A
小题5:B |
解析
没有证据表明一天之内除了饮用其他饮料外再喝八杯水会对你有益，事实是这可能对身体有害。
小题1:主旨题：从第一段的句子：Drinking eight cups or two litres of water a day is longstanding advice. But is there any scientific basis for it, asks Dr Chris van Tulleken.可知这篇文章讲的是：没有证据表明一个人每天要喝八杯水。选A。
小题2:猜词题：从第四段的句子：So they took a group of cyclists and exercised them until they lost 3% of their total body weight in sweat.可知dehydration是“脱水”的意思。选B。
小题3:细节题：从第八段的句子：there was no performance difference between those that were fully rehydrated and those that got nothing. 可知充分补水和什么都没有喝的人表现没有什么不同，选C。
小题4:细节题：从最后一段的句子：We are able to tolerate losses in water relatively well可知人类是可以忍受失去水的，选A。
小题5:细节题：从第一段的句子：But is there any scientific basis for it, asks Dr Chris van Tulleken.可知Dr Chris van Tulleken对长期以来对人们的建议是持有怀疑态度的，选B。 |
举一反三
Some kinds of mental skills naturally decrease as people get older. Yet research seems to show that some training can improve such skills. A recently published study also appears to demonstrate that the good effects of training can last for many years after that training has ended.
Researchers at Johns Hopkins University in Maryland wanted to learn how long memory and thinking skills would last in older people who trained to keep them. The people were part of the ten-year research project. They were taught methods meant to improve their memory, thinking and ability to perform everyday tasks.
More than 2,800 volunteered for the study called ACTIVE - short for Advanced (Cognitive) Training for Independent and Vital Elderly. Most studied when they were more than 70 years old.
The volunteers took one of several short training classes meant to help them keep their mental abilities. One class trained participants in skills including how to remember word lists. Another group trained in reasoning. A third group received help with speed-of-processing - speed of receiving and understanding information. A fourth group - the control group did not get any training.
Earlier results had established that the training helped the participants for up to five years. Now, lead study writer George Rebok says, the research showed most of the training remained effective a full ten years later.
Professor Rebok and his team found that the people trained in reasoning and speed-of-processing did better on tests than the control group.
"We are wondering whether those effects which endured over time would still be there ten years following the training, and in fact, that"s exactly what we found."
The effect on memory, however, seemed not to last as long. Still, the old people in any of the three classes generally reported less difficulty in performing daily activities than the control group. The total training time for the older people was between 10 and 15 hours.
小题1:Which statement is true according to the text？| A．This kind of training can only have effect on people for a few years。 | | B．The people were trained during a period of ten years. | | C．All the people who were studied were more than 70 years old. | | D．The second group were trained how to remember word lists. |
小题2:What can be inferred from the passage？| A．There were four groups being trained. | | B．The old people trained can remember words better. | | C．The second and third group improved their skills better than the first one. | | D．The research showed that the effect of the training could absolutely last 10 years. |
小题3:What’s the main idea of the fourth paragragh?| A．What was the meaning of the research? | | B．How was the research conducted? | | C．Why was the mental training effective? | | D．How long did the research last? |
小题4:What is the best title of the passage？| A．Mental Training Helped Elderly Stay Sharp for Years | | B．How to improve our mental health | | C．Four groups of old people were trained mentally. | | D． The result of a ten-year research |
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When I entered Berkeley, I hoped to earn a scholarship. Having been a Straight-A student, I believed I could tough subjects and really learn something. One such course was World Literature given by Professor Jayne. I was extremely interested in the ideas he in class.
When I took the first exam, I was to find a 77, C-plus, on my test paper, English was my best subject. I went to Professor Jayne, who listened to my arguments but remained . I decided to try harder, although I didn’t know what that because school had always been easy for me. I read the books more carefully, but got another 77. Again, I with Professor Jayne. Again, he listened patiently but wouldn’t change his . One more test before the final exam. One more to improve my grade. So I redoubled my efforts and, for the first time, the meaning of the word “thorough”. But my did no good and everything as before.
The last hurdle(障碍) was the final. No matter what I got, it wouldn’t cancel three C-pluses. I might as well kiss the goodbye. I stopped working hard. I felt I knew the course material as well as I ever would. The night before the final, I even myself to a movie. The next day I decided for once I’d have with a test. A week later, I was surprised to find I got an A. I hurried into professor Jayne’s office. He to be expecting me. “If I gave you the As you , you wouldn’t continue to work as hard.” I stared at him, that his analysis and strategy(策略) were correct. I had worked my head , as I had never done before. I was speechless when my course grade arrived: A-plus. It was the only A-plus given. The next year I received my scholarship. I’ve always remembered Professor Jayne’s lesson: you alone must set your own standard of excellence.
| 小题1: | | A．take | B．discuss | C．cover | D．get |
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| 小题2: | | A．sought | B．presented | C．exchanged | D．obtained |
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| 小题3: | | A．shocked | B．worried | C．scared | D．anxious |
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| 小题5: | | A．unchanged | B．unpleasant | C．unfriendly | D．unmoved |
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| 小题6: | | A．reflected | B．meant | C．improved | D．affected |
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| 小题7: | | A．quarreled | B．reasoned | C．bargained | D．chatted |
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| 小题8: | | A．attitude | B．mind | C．plan | D．view |
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| 小题9: | | A．choice | B．step | C．chance | D．measure |
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| 小题10: | | A．memorized | B．considered | C．accepted | D．learned |
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| 小题11: | | A．ambition | B．confidence | C．effort | D．method |
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| 小题12: | | A．stayed | B．went | C．worked | D．changed |
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| 小题13: | | A．grade | B．answer | C．lesson | D．comment |
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| 小题14: | | A．scholarship | B．course | C．degree | D．subject |
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| 小题15: | | A．helped | B．favored | C．treated | D．relaxed |
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| 小题16: | | A．fun | B．luck | C．problems | D．tricks |
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| 小题17: | | A．happened | B．proved | C．pretended | D．seemed |
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| 小题18: | | A．valued | B．imagined | C．expected | D．welcomed |
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| 小题19: | | A．remembering | B．guessing | C．supposing | D．realizing |
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Going on holiday not only makes you feel good while you’re there, you also gain the health benefits for months, new research shows．
Jetting off to destinations such as the Maldives cuts your blood pressure, helps you sleep better and bounce back from stress, it found．The benefits last at least a fortnight longer than the vacation and can be felt for months in some cases where it is claimed．Experts say workers should always take their full holiday entitlement（权利）each year, but as many as one in three don’t．
The study compared key health markers in holidaymakers visiting Thailand, Peru or the Maldives, with people who stayed at home and continued working．The average blood pressure of those on holiday dropped by six percent while the workers saw their blood pressure rise by two percent over the same period．The sleep quality of holidaymakers improved by 17 percent while that of the non-holidaymakers deteriorated by 14 percent．
The study also found the ability of vacationers to recover from stress, known as the stress-resilience test improved by 29 percent．There was a 71 percent fall in stress resilience scores among workers．Tests showed a fall in blood glucose levels, reducing the risk of diabetes （糖尿病）, trimmer waistlines and improved mood and energy levels, with the effects sustained for at least two weeks after returning home．
The Holiday Health Experiment was conducted by tour operator Kuoni and Nuffield Health, the UK’s largest healthcare charity．
小题1:According to the passage, how many people go on holiday? | A．Two thirds． | B．One third． | | C．17 percent． | D．A quarter． |
小题2:Which of the following can we infer from the passage?| A．The further you go, the better you get the benefits． | | B．Most people like to stay at home during the holiday． | | C．The result of the study is mostly based on the description from the people involved． | | D．Holiday makers are more adaptable than non-holidaymakers． |
小题3:The author intends to tell us that ________．| A．we have to go on holiday as much as possible | | B．you’ll certainly get depressed if you don’t go on holiday | | C．we had better go on holiday for the benefits of health | | D．it is best to go to foreign countries like Maldives |
小题4:The best title of the passage is ________．| A．A Holiday Health Experiment | | B．Health Benefits from Holiday | | C．Health Problems of Having Holiday | | D．Key Health Markers in Holidaymakers |
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Eight in 10 Americans eat fast food at least once a month and half eat it every week according, to a Gallup Poll. Yet most people who eat fast food know it’s bad for them. So why do they keep eating it?
The answer is simple: the benefits of eating fast food outweigh the long-term implications for most people. However, once you read these reasons why all those trips to the drive through may be slowly killing you, you may just want to stop eating fast food after all.
1. Fast food makes you fat.
A 15-year study of over 3,000 people found that eating fast food is linked to weight gain and insulin resistance. In others words, fast food makes you fat and increases your risk of type 2 diabetes. You probably know this already. But here’s something you may not know.
2. Fast food is addictive.
The more you eat fast food, the more you crave it. One study found that fast food is “a potentially addictive substance that is most likely to create dependence in vulnerable populations.” If you eat fast food once a week or more, you may be addicted to it.
3. Fast food is affecting your kids.
According to the CDC, childhood obesity has more than doubled in children and tripled in adolescents in the past 30 years. Kids have an amazing ability to recall ads they’ve seen. Fast food marketers know this, and design ads accordingly. Research shows strong associations between increases in advertising for non-nutritious foods and rates of childhood obesity.
4. Fast food “burgers” don’t have much burger in them.
One study found that most fast food burgers are composed of about 50 percent water and the actual meat content is only 2.1 to 14.8 percent. So what makes up the rest of it, you ask? Chemical fillers and preservatives, mostly. That’s why we see read horror stories about burgers that don’t go bad.
5. Even “healthy” fast food isn’t that healthy.
Fast food restaurants are catering to consumer demands to produce healthier options. The problem is, their definition of “healthy” is quite lax. One of the healthiest dishes at Burger King, the Garden Fresh Salad Chicken Caesar with TENDERGRILL Chicken and dressing, still has almost 500 calories and 28 grams of fat, and nearly a day’s worth of sodium.
6. Fast food is inhumane to animals.
Okay, this one may not be a reason why fast is killing you, but it’s still a compelling reason to stop eating fast food. 9 billion animals were slaughtered in the US alone in 2012 and much of that meat is for your fast food burgers and chicken sandwiches. Large factory farms resemble more of a “business” than a “farm.” Animals suffer in crowded spaces where they rarely have access to the outdoors or sunlight. They are pumped full of antibiotics to combat disease, which runs rampant in these conditions. Livestock is one of the biggest sources of pollution and environmental negligence, according to the UN.
7. Fast food sodas are loaded with sugar.
High fructose corn syrup (HFCS) is the cheap sweetener most fast food restaurants use in their sodas, desserts, and many other products. Princeton University researchers linked HFCS consumption to obesity in an animal study. Rats given HFCS gained more weight and body fat than those given table sugar.
小题1:How many factors are mentioned which can account for the reason why fast food is slowly killing you?| A．Seven. | B．Three. | C．Four. | D．Five. |
小题2:According to the text, we know that_____.| A．many people keep eating fast food because they know nothing about the harm which fast food will bring them | | B．fast food plays a key role in children’s growth | | C．eating fast food is connected to weight gain and insulin resistance. | | D．many fast food restaurants are can offer a good and healthy meal to consumer |
小题3:What is the purpose of the passage?| A．To help us make right decisions | B．To advise us to stop eating fast food | | C．To tell us how to keep fit | D．To encourage us to be humane to animals |
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Last summer, when Amanda R of Anaheim Hills, California, was running on a cross-country course with her team, she blacked out. “I got really dizzy,” she says. “I was out for a few minutes.” At first, Amanda thought she was just tired and didn’t think she had a health problem. She did go to the emergency room, where she was fine after tests, but she fainted (昏厥) again several days later as she was talking with her coach. Another doctor guessed that Amanda had blacked out “because we were in heat so much with not enough water and not enough of the right kind of foods”.
Teens often don’t want to stop and take a break or don’t notice when they start to feel bad, doctors say. However, paying attention if you’re not feeling well is important, as Amanda learned.
As a result, Amanda has changed her habits. “I drink a lot more water,” she says. “And put more salt in my diet. I’m eating more balanced meals.” Amanda advises teen athletes to trust their coaches and speak up when they’re not feeling well. “And recognize the difference between when you’re tired and when there’s something really wrong.”
Some people － up to 3 percent of the population － sweat too much, even in cold weather. The condition, called hyperhidrosis (多汗), can affect many parts and it often runs in families － hands down from generation to generation. Too much sweating over the whole body could be a symptom of another medical condition. Doctors aren’t sure what causes hyperhidrosis, but using special medications or other treatments can help.
小题1:What caused the happening mentioned in the passage during Amanda’s running?| A．She couldn’t breathe in enough air in the race. | | B．She didn’t eat anything before the race. | | C．She had been running all summer without a rest. | | D．She neither drank enough water nor ate enough of the right kind of foods. |
小题2:What can we infer from Paragraph 4?| A．There is no need to worry when sweating too much, even in cold weather. | | B．Hyperhidrosis may have a bad effect on your health. | | C．Doctors have discovered why people get hyperhidrosis. | | D．Hyperhidrosis is a serious disease and no treatment can help. |
小题3:The purpose of writing this passage is to____________.| A．tell teens the proper ways to take exercise in summer. | | B．tell teens not to run in hot summer. | | C．tell teens to pay attention to hyperhidrosis in the summer exercise | | D．tell teens how to keep healthy. |
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