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A
American children aren’t the only couch potatoes with nearly one third of children globally spending three hours a day or more watching TV or on computers, according to a study of over 70,000 teens in 34 nations.
From Argentina to Zambia, Regina Guthold of the World Health Organization in Geneva and her colleagues found most children aren’t getting enough exercise and it made no difference whether they lived in a rich or a poor country. “With regard to physical activity levels, we did not find much difference between poor and rich countries,” Guthold said. The study looked at 72,845 schoolchildren aged 13 to 15 from North and South America, Asia, Europe, Africa and the Middle East.
The researchers explained that plenty of physical activity means at least an hour of exercise outside of gym class at least five days a week. Children who spent three or more hours a day watching TV, playing computer games, or chatting with friends online—except for time in school or time spent doing homework—were classified （归类） as sedentary.
The researchers found only one quarter of the boys and 15 percent of the girls were getting enough exercise by these explanations. A quarter of boys and nearly 30 percent of girls were sedentary and didn’t get enough exercise with girls less active than boys in every country except for Zambia.
Uruguay had the highest percentage of active boys, at 42 percent, while Zambia had the lowest, at 8 percent. Girls from India were the most active, with 37 percent getting enough exercise, while girls from Egypt were the least active, with just 4 percent getting plenty of exercise. Children in Myanmar were the least sedentary, with 13 percent of boys and 8 percent of girls classified as sedentary. The most sedentary nations were St. Lucia and the Cayman Islands, with 58 percent of boys and 64 percent of girls spending at least three hours a day in sedentary activity.
People showed a deep concern for kids’ lack of physical activity in various nations. Why do they he a low level of physical activity? Guthold thought that urbanization （都市化） could be a factor as well as access to cars and TVs.
1. What do we know about the findings of the study led by Guthold?
A. Girls in every country are no more active than boys.
B. Only 4 percent of girls from Egypt are not active exercisers.
C. Children in rich countries get less exercise than those in poor countries.
D. Only a all percentage of children around the world do enough exercise.
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跟踪导练（五）
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