Endurance running might have played an important role in human evolution. In a report in the journal Nature, researchers Dennis M. Bramble of the University of Utah and Daniel E. Lieberman of Harvard University found that humans can compete with almost any animal on Earth, even horses, if the race is long enough. "They have this enormous endurance and range," Bramble said.
Anthropologists have long regarded humans' ability to walk as a defining evolutionary characteristic, while running was seen as a biological afterthought. Not so, Bramble said. Humans are pitiful sprinters but well-suited for endurance running, with long legs; large joints to absorb shock; thick, springy tendons; small forearms that are easy to hold aloft; an ability to twist the trunk and head to improve balance; and relatively hairless bodies to dissipate heat.
Bramble said the fossil record suggests human ancestors probably began jogging about 2 million years ago in Africa, but it's unclear why.
-- Washington Post