Many of us sit in front of a computer for eight hours a day, and then go home and head for the couch to surf the Web or watch te

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问题     Many of us sit in front of a computer for eight hours a day, and then go home and head for the couch to surf the Web or watch television, exchanging one seat and screen for another. Even if we try to squeeze in an hour at the gym, is it enough to counteract (抵消) all that motionless sitting?
    A mounting body of evidence suggests not.
    Increasingly, research is focusing not on how much exercise people get, but how much of their time is spent in sedentary (久坐的) activity, and the harm that does.
    The latest findings, published this week in The Journal of the American College of Cardiology, indicate that the amount of leisure time spent sitting in front of a screen can have such an overwhelming, seemingly irreparable (无法弥补的) impact on one’s health that physical activity doesn’t produce much benefit.
    The study followed 4,512 middle-aged Scottish men for a little more than four years on average. It found that those who said they spent two or more leisure hours a day sitting in front of a screen were at double the risk of a heart attack or other heart events compared with those who watched less. Those who spent four or more hours of recreational time in front of a screen were 50 percent more likely to die of any cause. It didn’t matter whether the men were physically active for several hours a week — exercise didn’t reduce the risk associated with the high amount of sedentary screen time.
    The study is not the first to suggest that sedentary activities like television viewing may be harmful. A 2009 study reported that young children who watch one and a half to five and a half hours of TV a day have higher blood pressure readings than those who watch less than half an hour, even if they are thin and physically active.
    Recreational screen time has an "independent, injurious relationship" with heart and the blood vessels events and death of all causes, the paper concluded, possibly because it induces metabolic (新陈代谢) changes.
    The study focused on recreational screen time because it’s the easiest to reduce, Dr. Stamatakis said. But he encouraged employees who work at computers all day to get up and take breaks and short walks periodically.
According to the passage, more and more evidence proves that______.

选项 A、people doing regular exercises after work tend to enjoy good health
B、people nowadays seem to spend excessive time seated at home
C、the time people spend watching TV is increasing dramatically
D、physical activities don’t reduce the bad effect of long time’s sitting

答案D

解析 根据题干中的evidence将本题出处定位到第二段。首段末句提到:即使我们想方设法挤出一小时去健身房,是否就足以抵消这整天静坐不动对健康所造成的影响呢?第二段对该问题进行了回答:越来越多的证据表明不能。由此可知,体育锻炼并不能减轻久坐不动造成的不良影响,故答案为[D],同时排除[A]。文中提到人们下班后坐在家里的沙发上看电视,但并未提及人们在家坐着的时间过多或是看电视时间急剧增加,故排除[B]和[C]。
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