Take “The Belly Button Challenge” [VIDEO]

Innie or outie?

Another wacky challenge is taking the internet by storm and what started in China, has now spread to the U.S. and beyond.

"The Bellybutton Challenge" involves reaching one hand behind the back and reaching around the front to touch your bellybutton. If you can do this, supposedly you are in tip-top shape and if you can't, it may be time to lay off the donuts, or that cake I passed in the hallway at work this morning.

However, experts say that it doesn't mean you are super fit, you just may have very long arms and great flexibility. Or judging from these videos, you need to weigh about 90 pounds.

Naturally, everyone who completes this, then posts a selfie.