Humans are built for running without shoes, as the famed Raramuri runners of Mexico show even today

The Raramuri of Mexico start running at a young age, and run their entire lives. They run great distances while barefoot or with just thin sandals. How do they do it without modern running shoes? It's easy, says an expert on physiology and barefoot running. My sidebar on barefoot running to go with a larger story on ESPN.com about the Raramuri's prowess. http://www.espn.in/olympics/story/_/id/20770226/why-human-foot-was-made-running-long-distances-even-shoes