Unit 3 On the move 单元拓展-【正禾一本通】2023-2024学年新教材高一英语必修第二册同步课堂高效讲义教师用书（外研版2019）

一、单元主题升华阅读 　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　 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 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 runners' knees, 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 an experienced racer to learn proper technique，” she says.“It takes some practice.” 语篇解读：本文是一篇说明文。短文介绍了竞走相比跑步有诸多的优势，但是之前受过伤的人，要想进行这项运动要谨慎，最好咨询专家的建议。 1．Why are race walkers conditioned athletes? A．They must run long d