2020年全国I卷
C
Race walking shares many fitness benefits with running, research shows, while most likely contributing to fewer injuries. It does, however, have its own problem.
Race walkers are conditioned athletes. The longest track and field event at the summer Olympics is the 50-kilometer race walk, which is about five miles longer than the marathon. But the sport’s rules require that a race walker’s knees stay straight through most of the leg swing and one foot remain in contact (接触) with the ground at all times. It’s this strange form that makes race walking such an attractive activity, however, says Jaclyn Norberg, an assistant professor of exercise science at Salem state university in Salem, Mass.
Like running, race walking is physically demanding, she says. according to most calculations, race walkers moving at a pace of six miles per hour would burn about 800 calories(卡路里) per hour, which is approximately twice as many as they would burn walking, although fewer than running, which would probably burn about 1,000 or more calories per hour.
However, race walking does not pound the body as much as running does, Dr. Norberg says. According to her research, runners hit the ground with as much as four times their body weight per step, while race walkers, who do not leave the ground, create only about 1.4 times their body weight with each step.
As a result, she says, some of the injuries associated with running, such as runner’s knee, are uncommon among race walkers. But the sport’s strange form does place considerable stress on the ankles and hips, so people with a history of such injuries might want to be cautious in adopting the sport. In fact, anyone wishing to try race walking should probably first consult a coach or experienced racer to learn proper technique, she says. It takes some practice.
28. Why are race walkers conditioned athletes?
A. They must run long distances.
B. They are qualified for the marathon.
C. They have to follow special rules.
D. They are good at swinging their legs.
29. What advantage does race walking have over running?
A. It’s more popular at the Olympics.
B. It’s less challenging physically.
C. It’s more effective in body building.
D. It’s less likely to cause knee injuries.
30 What is Dr. Norberg’s suggestion for someone trying race walking?
A. Getting experts’ opinions.
B. Having a medical checkup.
C. Hiring an experienced coach.
D. Doing regular exercises.
31. Which word best describes the author’s attitude to race walking?
A. Skeptical.B. Objective.
C. Tolerant.D. Conservative.
答案解析：
28. C. 根据第二段的内容，尤其是提到了竞走运动员在比赛时必须遵守的规则："a race walker’s knees stay straight through most of the leg swing and one foot remain in contact with the ground at all times."这表明竞走运动员需要遵循特殊的规则。因此，选项C是正确的。
29. D. 根据第四段的内容，尤其是提到了竞走与跑步相比，对身体的冲击较小，而且像跑步者膝这样的伤害在竞走运动员中不常见。因此，选项D是正确的。
30. A. 据最后一段的建议，"anyone wishing to try race walking should probably first consult a coach or experienced racer to learn proper technique"可知，Norberg博士建议想要尝试竞走的人应该首先咨询教练或有经验的运动员来学习正确的技巧。因此，选项A是正确的。
31. B. 整篇文章中，作者提供了关于竞走的利弊的信息，没有表现出偏见或强烈的个人情感，而是以一种客观的方式介绍了竞走这项运动。因此，选项B是正确的。
