First came the Belly Button Challenge. Then it was a long legs test. Next up came a collarbone competition, plus feats to demonstrate the depth of one’s dimples and the fullness of one’s eyelashes.

In recent weeks, Internet users in mainland China have been going gaga over online memes supposedly aimed at testing – or telegraphing – how fit and attractive one’s figure is. While being chubby was once regarded as a sign of health and wealth in a country frequently beset by famine, China in recent years has witnessed a growing body-consciousness, with weight-loss clinics, breast-enhancement centers and plastic surgery hospitals all gaining in popularity.

As China has urbanized and modernized, it has also grown fatter. A study by researchers at the University of Washington published last year in the journal the Lancet found that 28% of Chinese men and 27% of women were overweight or obese. The rate of childhood obesity has also been rising at an alarming clip.

The Belly Button Challenge peaked in mid-June, with thousands of people posting selfies showing their attempts to touch their navels by reaching one arm around their backs in a yoga-style pose. To date, the topic has garnered more than 130 million hits on Weibo, China’s Twitter-like microblogging service.

Exactly what touched off the Belly Button Challenge remains unclear, though some online postings claimed “U.S. scientists” had “discovered” that the inability to complete the feat was an indicator that one needed to slim down.

A variety of celebrities – mostly super-slim young women with narrow waists – seized the opportunity to post photos of themselves in the pose; tour guides in Hunan province posed for pictures of themselves in red bikinis contorting themselves like pretzels. A young woman in Chongqing – who weighs about 100 pounds and stands about 5 feet 1 -- spent days trying to complete the challenge but ended up with a dislocated shoulder, the Chongqing News reported.

State-run media have reported on the trend and tried to tamp it down a bit, with the Communist Party mouthpiece People’s Daily quoting a personal trainer in Nanjing as saying that the ability to complete the test might just mean one is rather flexible or simply has long arms. “I can’t do it either,” said the trainer, Xie Wei.

Others have mocked the trend. In one widely reposted message, one commentator urged Chinese to go ahead and eat. American scientists, he joked, had discovered that some primates were incompletely evolved, with their “excessively long arms not accustomed to walking upright.”

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FOR THE RECORD

8:32 p.m.: An earlier version of this post incorrectly said Chinese actor Tong Dawei posted the message urging people to eat.

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But netizens have just seemed to move from gazing at their navels to other parts of their physiques.

When 24-year-old Chinese Canadian singer Kris Wu, 6 feet 2, posted a photo of himself stretched out on a couch, his legs occupying the entire sofa, it set off another viral fad. Fans issued a challenge to others to sit with friends on a couch and see how many people their legs could stretch across.

Inveighed the state-run China Daily: “People with long limbs are simply born that way, and for those with short limbs, stretching over many people on a couch will have to remain a distant dream.”

Next up came the collarbone challenge, with young women showing off the depths of their clavicle hollows by filling the depressions with stacks of coins or even eggs.

Critics of the trend – a resurrection of a fad that first surfaced two years ago – said the collarbone meme was just an opportunity for attention-starved youths to draw attention to their chest areas from their bare midriffs.

Those with neither flat bellies nor sexy necklines, however, were not to be left out. Up next came women showing off the depths of their dimples by demonstrating how they could hold pen-caps in their cheek depressions, and others balancing multiple Q-tips or toothpicks on their eyelashes.

Chinese Internet users also took the opportunity to repost photos from this spring’s short-lived “Hold a Coke Can With Your Breasts” challenge, which was initially touted as a breast-cancer awareness project but was later revealed to have been initiated by an American adult entertainment casting company.

“Put Coke between your breasts and coins on collarbones, reach your bellybutton from behind, keep the pen cap in your dimples, leave toothpicks on your eyelashes,” one fed-up Chinese Internet user wrote on Weibo. “I’d like to report you monsters who can do all these to the police.”

Nicole Liu and Harvard Zhang in The Times' Beijing bureau contributed to this report.