- [Narrator] Cheetahs are the fastest land animal
in the world.
But did you know that humans can leave them in the dust?
At least in the long run.
That's right, when it comes to endurance,
we can outrun wolves, cheetahs, and even horses.
Now in the beginning, humans fall short,
because we're lousy sprinters.
Case in point, Usain Bolt couldn't outrun a cheetah
in the 100-meter dash if he wanted to.
And he tried.
But marathons and ultra-marathons
are a whole other ball game.
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.
So what makes humans such endurance running superstars?
The secret weapon is our sweat.
We have two to four 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 gate 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.
Some of it goes into vibrations and sound
as we strike the ground,
but most of it actually goes straight to our tendons.
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 to 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 how did humans get to be such great endurance runners?
Some anthropologists believe this became important
around two to three million years ago,
when we started hunting and scavanging.
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.
In fact, persistence hunting remained in use until 2014,
such as with the San people of the Kalahari Desert.
But distance running can still help you,
even if you're not interested
in running down your next meal.
Studies show running can lower body weight,
body fat, and cholesterol levels.
And the longer you train, the greater the health benefits.
Just one year of training has been shown
to reduce body weight by about seven pounds,
lower body fat by 2.7%,
and decrease resting heart rate by 2.7%.
It may seem really hard,
or maybe even impossible to run a mile or a marathon.
But in fact, you were born to go on that run.
We all were.
(upbeat music)