I find it interresting that no one questions the "we are born to run" claim. I have seen very little evidence for that.
There is a link to a study in the first paragraph of the article:
http://news.nationalgeographic.com/news/2004/11/1117_041117_...
> The researchers identified a range of physical traits that suggest human ancestors evolved as distance runners. The adaptations helped them chase down prey and compete more effectively with the speedier carnivores on the open plains of Africa, the study says.
> The researchers say adaptations for running stretch back more than two million years, allowing humans to evolve from our apelike ancestors Australopithecus.
> "We think running is one of the most transforming events in human history," Bramble added. "We are arguing the emergence of humans is tied to the evolution of running."