The Shoe That Could Make a Sub-Two-Hour Marathon Possible

[Narrator] This is the shoe Nike claims

can make any runner 4% faster.

It's called the Vapor Fly 4%.

We've shown these to some of our external partners,

and they've helped measure them

and independently verify them.

I think, even from a science perspective,

their best scientifical term was

they're just magic.

[Narrator] To prove just how magic,

Nike is attempting to break

the last great barrier in running,

a marathon completed in under two hours.

It's a little bit like the sub-10-second 100 meters.

It's a little bit like the four minute mile.

It's one of those big barriers for kind of human potential.

[Narrator] In the past century,

elite marathoners have shaved close to an hour off

the world's best time.

The current record stands at two hours, two minutes

and 57 seconds.

Those last three minutes might not seem like much,

but they're the difference between what is

and isn't humanly possible.

That's Eliud Kipchoge.

He's one of the best long distance runners in the world.

Nike signed on him and two other athletes,

Zersenay Tadese and Lelisa Desisa,

to try and break two hours.

[Matthew] I think the first reaction from

most of the runners who've seen them,

just visually, is they don't look like a traditional shoe.

They're a little bit thicker than they're used to.

Certainly when they hold them,

they're a little bit stiffer than they're used to.

And maybe in prototype phase,

they're not as pretty as they're used to.

[Narrator] Nike worked on that,

and these are the custom designed Vapor Fly Elites.

You won't find these in stores.

They were specifically tailored for the three runners

to wear on race day.

Inside the shoe, there are two key innovations.

The sole is made from a foam that's very light

but still thick enough to support the foot.

You want the athlete to be able to

take the dampening, the suspension from their body,

and sort of dissipate that through the foam,

but then, you also want that propulsion back out.

So we have this amazing foam that does both of those,

like no other foam that we've ever used in the past.

[Narrator] Second, the sole is embedded

with a carbon fiber plate that helps with propulsion.

So, think of a spike plate,

something that really helps propel you

through the next stride.

It's pretty stiff.

It's also very, very thin and very, very light,

but you can tune that specifically to your athlete's needs

and your running gaits.

[Narrator] But can an athlete really 4% faster

just by putting on a pair of shoes?

If everything is done properly,

then I think that this is a possibility.

[Narrator] That's Benno Nigg.

He's an independent expert in biomechanics.

He's conducted studies on the benefit

of using plates in running shoes.

We have a lever here

that is about from the ankle joint

to that point here.

Now if we have a plate,

then make that plate a little bit stiff,

a little bit longer, then we can increase that lever.

And you can imagine that when the lever is bigger,

that you have an advantage in performance.

[Narrator] While Nigg hasn't seen the shoes,

he says that if they are to have a major impact,

Nike will have to tune the angle of the plates

to the gait of each athlete.

The question is whether they do the right thing,

and that's not easy.

That's very complicated.

The tuning of a shoe for an athlete

is not an easy thing.

[Narrator] The shoes aren't the end of Nike's plan.

To control as many variables as possible,

the athletes aren't running in a big city marathon.

Instead, Nike is putting on its own event

at a racetrack in Monza, Italy.

So I'm super confident in the product,

but I also know that that's gotta translate

to the human beings that are actually

putting themselves on the line and in that day.

But we're doing everything we can

to put them on the start line

to better achieve their goal.

[Narrator] There's just a few weeks left

to get everything right.