Americans spent $59 million on "minimalist" running shoes last year, on the premise that the most healthful way to run is the way people have done it for thousands of years: barefoot.
Running barefoot, according to the hugely popular 2009 book "Born to Run" and a landmark 2010 study of Kenya's famous Kalenjin distance runners, forces most people onto their forefeet, which nature designed to absorb the considerable impact that running places on feet and lower legs. Traditional running shoes of the past 40 years, in contrast, encourage runners to land on that cushy, raised heel, possibly contributing to lower leg problems.
But now a group of George Washington University researchers, who tested a different population of barefoot African runners, has determined that most of them naturally strike the ground with their heels.