on the stupid, but every now and then,

we get the chance to study at the feet,

or in this case, the hands of a real expert.

Meet Kevin from Switzerland.

He's going to try and set a Guinness World Record title

for the fastest descent of 50 stairs

while walking on his hands.

Good luck, Kevin.

[music playing]

[cheering]

Wow, 14.58 seconds.

I couldn't run it in that time.

Don't forget, the problem with walking on your hands

is there's nothing to catch you when you fall,

and for most people, falling is almost inevitable

[thud]

if you can get up in the first place.

Ah, that's much better.

[thumping]

Yeah, really well.

I would advise quite strongly that you don't try this.

The thing is Kevin knew science, and when you know science,

it's just like a walk in the park, only

upside down, on your hands, and not necessarily in a park.

First, he swings his legs upwards,

generating just enough angular momentum

to stay balanced upside down.

His arms must be strong enough to support his weight.

Being upside down can be disorienting as the vestibular

system located in the inner ear sends signals

to the brain telling him he's inverted,

meaning he must concentrate more to stay oriented.

Going downstairs, he generates more angular momentum, which he

balances out by going down quickly

and moving his arms, his base of support

under his center of mass.