new challenge and style of photography that has taken to Weibo by surprise, the most popular social network in China and the trend threatens to other platforms, including Twitter.

What is the challenge? Simple, users, both men and women must prove they can touch the navel round the waist in the back with one hand.

At first glance it seems an easy challenge, but for many it is impossible and frustrating, and therein lies their success and viralization, as this has generated a series of questions.

However, experts suggest that failing to realize this challenge does not indicate that you are overweight or have health problems, but because your flexibility of the shoulder joint is not as good.