Researchers from the JKM Technologies Company in Virginia, the University of Virginia and the University of Colorado did the study.

　　They found that running shoes create more stress that could damage knees, hips and ankle joints than running barefoot. They observed that the effect was even greater than the effect reported earlier for walking in high heels.

　　The study appeared in the official scientific journal of The American Academy of Physical Medicine.

　　The other study appeared in the journal Nature. It compared runners in the United States and Kenya. The researchers were from Harvard University in Massachusetts, Moi University in Kenya and the University of Glasgow in Scotland.

　　They divided the runners into three groups. One group had always run shoeless. Another group bad always run with shoes. And the third group had changed to shoeless running.

　　Runners who wear shoes usually come down their heel first. That puts great force on the back of the foot. But the study found that barefoot runners generally land on the front or middle of their foot. That way they ease into their landing and avoid striking their heel.

　　Harvard's Daniel Lieberman led the study. He says the way most running shoes are designed may explain why those who wear them land on their heel. The heel of the shoe is bigger and heavier than other parts of the shoe, so it would seem more likely to come down first. Also, the heel generally has thick material under it to soften landings.

【2017届高考英语一轮复习练习：必修4 Module 3 Body Language and Non-verbal Communication（外研版）】相关文章：

★ 【北京专用】2014届高考英语一轮复习方案课时作业：必修1 Unit 4 Earthquakes

★ 【人教版】2014届高考英语一轮复习指导考点针对练：选修8 unit4《Pygmalion》

★ 【浙江专用】2014届高考英语一轮复习课时作业(十三)必修3Unit 3《The Million Pound Bank Note》

★ 2017届江苏省淮安市新马中学高考牛津译林版英语一轮复习活动单：模块8 Unit 3《The world of colours and light》

★ 2017届高考英语二轮复习书面表达限时测验：6（含解析）

★ 2014届高考英语一轮复习课时作业(三十八)选修7Module 2《Highlights of My Senior Year》（外研版）

★ 2017届高考英语二轮复习课时训练：12（含解析）

★ 【人教版】2014届高考英语一轮复习指导考点针对练：选修7 unit4《Sharing》

★ 【人教版】2014届高考英语一轮复习指导考点针对练：必修5 unit1《Great scientists》

★ 2014届高考英语一轮复习选修6参考答案（外研版）