(2020·全国卷Ⅰ·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 50kilometer 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.
【语篇解读】 本文是一篇说明文。主要介绍了竞走这项运动的相关情况及其与跑步的不同之处。
1．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.
C [推理判断题。由题干中的关键词conditioned athletes可将解题信息定位至第二段，根据该段中的“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.” 可知，竞走运动的规则要求竞走者的膝关节在腿摆动时的大部分时间里伸直，同时一只脚保持与地面接触。据此可知，竞走者必须遵循一些特殊的运动规则，故C项正确。]
2．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.
D [细节理解题。根据第五段中的“some of the injuries associated with running，such as runner's knee，are uncommon among race walkers” 可知，一些与跑步有关的损伤，如跑步者的膝盖(受伤)，在竞走者中并不常见。据此可知，竞走不太可能导致膝盖受伤，故D项正确。]
3．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.
A [细节理解题。根据第五段中的“anyone wishing to try race walking should probably first consult a coach or experienced racer to learn proper technique” 可知，Norberg博士建议任何希望尝试竞走的人或许应该首先咨询下教练或有经验的竞走者，以学习正确的技巧，故A项正确。]
4．Which word best describes the author's attitude to race walking?
A．Skeptical. B．Objective.
C．Tolerant. D．Conservative.
B [观点态度题。根据全文内容可知，作者提到了竞走这项运动的好处，同时也指出了它的一些危害，态度是客观的，故B项正确。]
