Well, there’s a new fad sweeping the land—China, that is—and it’s a weird one.

According to BBC.com, the challenge that launched 104,000 discussion threads and is the top trending topic on Weibo (China’s Twitter) translates as “reaching your belly button from behind to show your good figure.”

Dubbed the belly button challenge for short, this odd social media trend involves wrapping your right arm around your back to touch your bellybutton. Sounds like a roadside sobriety test, right? Wrong. If you can successfully reach your naval, you’re nice and fit. If you can’t, you need to lose weight.

Eye roll.

According to Daily Mail UK, users gleaned this oh-so-wise conclusion from a “scientific study from the US.” Sounds legit.

Sough Sa tries the challenge (Image: BBC, Weibo)

More than 130 million users have already participated, many of them young, female, thin, and midriff-baring, but the real hero of the trend is male Weibo user Sough Sa, who, according to BBC.com, noted “Is this trend really that difficult? I don’t think so.” A few other guys with average figures joined in, as well.

But don’t scrap your lunch for lemon cayenne water just yet; this seems to be more a test of your flexibility than anything else.

According to Daily Mail UK, Xie Wai, a fitness instructor from China, has set the record straight in an interview with People Daily Online, noting that there’s actually three things at play here: flexibility, long-ass arms and sure, thinness.

The hashtag #bellybuttonchallenge has made its way to Instagram, but if you’re going to try the borderline body shaming challenge (yeah, of course we did), make sure you take it lightly.

Featured image: Daily Mail UK

Would you try the belly button challenge? Let us know in the comments below, or tweet us @ViewtheVibe.