Do you remember the belly button challenge? How about the pen under boob challenge? These are only few of the bizarre social media craze that went viral online. And recently, another trend took the Chinese internet by storm showing women covering up their waists with a sheet of paper. While the trend seems odd, this is to prove how fit they are.

The craze called “A4 Waist Challenge” aims to prove one’s fitness or womanhood.

A4 Waist Challenge c

The idea of the challenge is simple, all you have to do is compare your waist to an A4 paper…

A4 Waist Challenge b

Which measures 21cm in width and 29.7cm in length.

A4 Waist Challenge a

If you can hide your waist with the paper positioned vertically without any tummy sticking out, congratulations, you’re in good shape!

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Women taking part of the trend believe that the challenge is a very reachable and healthy goal to aim towards.

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They also believe that fit is the new sexy.

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The bizarre social media craze has become a hot trend on Sina and Weibo with hundreds of women showing off their paper-thin waists.

A4 Waist Challenge 1

Does the “A4 Waist Challenge” really proves how sexy you are?

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However, just like the past silly fitness challenges, some social media users have slammed it as ‘worrying’ and ‘wrong’, saying this fitness trend is unrealistic.

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H/T: Shanghaiist, Mirror