论跑步耐力人类远胜其它物种

Each year, a small town in Wales holds the Man Versus Horse Marathon. It's a 22-mile race between riders on horseback and runners. And, while horses often win, humans will sometimes prevail.

威尔士的一个小镇每年都会举办“人马长跑大赛”，由骑马者和跑步者共同参与，赛程约为35公里。虽然骑马者常常胜出，但人类有时也能获胜。

So what makes humans such endurance running superstars?

The secret weapon is our sweat. We have 2-4 million sweat glands all over our body, which means we can run and cool ourselves at the same time. Having no fur is also a huge plus.

In contrast, dogs rely on panting to cool down, and other animals, like horses and camels, also sweat, but less effectively. As a result, they overheat faster and must slow down sooner.

The mechanics of our running stride also makes us particularly well-suited for endurance running. A human's running gait has two main phases: Aerial when both feet are off the ground and Stance when at least one foot touches the ground.

While in the air, gravity pulls us down, which generates a lot of kinetic energy. However, the second we hit the ground, we instantly decelerate, losing that kinetic energy in the process.

Here's where our special adaptations come in. The tendons and muscles in our legs are very springy. They act like a pogo stick, converting kinetic energy from the aerial phase into elastic potential energy, which we can use later.

In fact, our IT band can store 15-20 times more elastic energy than a chimpanzee's similar body part, the fascia lata. When it comes time to step off, those springy tendons can turn 50% of that elastic pogo-stick energy back into kinetic, making it easier to propel forward. Without that extra energy, we'd have to exert that much more effort just to take a step.

So, why did humans get to be such great endurance runners, anyway?

Some anthropologists believe this became important around 2-3 million years ago, when we started hunting and scavenging. Because we couldn't chase down a gazelle like a cheetah, early humans learned persistence hunting. Where they would track prey over long distances until the prey either overheated or was driven into a trap.