Washington - Harvard biologist and runner Daniel Lieberman had a simple question: "How did people run without shoes?" The answer: Much better. At least running barefoot seems better for the feet, producing far less impact stress compared to feet shod in expensive running shoes, according to Lieberman's study in today's issue of the journal Nature. The research was funded in part by a company that makes minimalist running shoes to mimic barefoot running. But Lieberman said the company had no say in the design of the study and didn't influence the outcome. People who grew up running barefoot, such as boys in Kenya, who are known as endurance running champs, tend to land mostly on the front or middle of the foot. People who have always worn running shoes hit the ground heel first. The difference is important. The study found that people with running shoes strike the ground with the mass of the entire leg, nearly 7 percent of the body. That's more than three times the weight of impact for barefoot running. For runners in shoes, it's "like someone hitting you on the heel with a hammer," he said. -Associated Press

-Associated Press