Humans

Max Speed:

Average Speed for 20+ Miles:

Best Marathon Time:

27.45 mph (Usain Bolt, 100 meters)12.7 mph (Haile Gebrselassie)2:03:59 (Haile Gebrselassie, Berlin)Are humans born to run ? Some experts think that humans have, indeed, evolved to be distance runners—the better to track prey, evade predators and migrate. While there is some debate on running and human evolution, there is no question that we are up there in the animal kingdom for speeds at marathon distances. There is no one reason, but the efficiency of our cooling systems—our ability to sweat—and having an upright posture, to minimize our sun exposure and maximize our lung capacity, are some of the primary reasons we are skilled distance runners.One major difference between humans and animals is that we don't have in-born endurance; we have to train. Peter Weyand says that compared to other animals, humans have a high energy cost of running—we spend more energy in each stride relative to our size. But unlike wild animals, we can motivate ourselves to run, and through training we can increase our aerobic scope—the amount of aerobic activity one can achieve. "Even though [humans] are good at regulating heat, they have more heat to dump because their economy is poor," he says. Strict training regimens and the ability to sweat can make up for that lack.