He has exposed himself at the site of China's deadliest high speed rail crash in 2011
The artist has taken more than 700 photos capturing his nude exercises on streets in China and sometimes abroad -? a body of work unmatched in the contemporary art world.
But the locations he chooses -? sites of government abuses, protests and disaster -? show there is more to his work than just cheek.
"My aim isn't to get people to look at my press-ups, but to use a method to get society to think," said the 46-year-old, clothed in a white polo shirt and jeans for a dim-sum lunch in his hometown of Guangzhou.
Taken as a whole, Ou's work presents an alternative history of China's last decade " highlighting "sensitive" events that Communist authorities would rather play down.
One 2008 photo shows him naked opposite the grey office of a milk powder company at the heart of a scandal which sickened some 300,000 babies that year. Pedestrians walk by opposite apparently oblivious.
Three years later, he stripped at a patch of scrubland near the village of Wukan in southern China, where villagers had risen up against local officials in protest at land grabs.
He has exposed himself at the site of China's deadliest high speed rail crash in 2011, anti-Beijing protests in Hong Kong in 2014, and chemical explosions in Tianjin last year.
All the events were covered by China's state-run media, but in a heavily censored form which shifted blame away from central authorities.
"The aim is to make the public remember these incidents," he said. "People know, if there is a place where something happens, I should make an appearance there."
A TV producer, Ou started experimenting with naked photography on work trips to foreign hotels "as a way of reliving stress", before his first outdoor shot on China's Great Wall in 2005.
As a method of physical exercise, the press-ups are meant to symbolise "building social strength".
Perhaps surprisingly, despite its sensitivity Ou has been able to distribute his work on China's closely controlled internet, and its oblique nature has enabled it to be featured in China's tightly censored domestic press.
He has been chased by dogs and had run-ins with local police ?- who on several occasions have detained him and told him to delete photographs.
Last year, he was nabbed by officers outside a cottage in southern China where four children drank pesticide after being abandoned by their migrant worker parents, and only released once he flashed his press credentials.
"As soon as I took the photo, a car pulled up and took me away," he said.
He credits the survival of his work to his avoiding explicit verbal criticism of Communist authorities, letting his photos speak for themselves with simple titles stating their location and the incident in question.
But China's online population ?- who remember incidents even after reports on them are deleted, get the message.
"Using nudity brings a force to his art, it shows the force of an individual in the face of powerful public architecture," said art critic Li Xianting.
Ou acknowledges the risks. "You have to be careful... at the moment I'm safe," he said.
"You need to do things which are meaningful for society. It can open a window, and be shared by ordinary people. That's already a kind of change."
Straddling art and journalism ?- winning a commendation at the World Press Photo Awards in 2010 -- his work was the subject of a major exhibition in Venice last year.
"His 'impertinent' nudity is a protest against the arrogance and neglect of power to the society and people," Chinese art critic Gu Zheng said in the exhibition catalogue.
The artist has not had a large-scale exhibition on the mainland, saying he prefers to distribute his work online.
He updates an account on social media service Wechat with his thoughts on China's latest scandals -- from the death of an academic in police custody to the 50th anniversary of the destructive Cultural Revolution.
Most are accompanied by a image from his collection, picked to match the topic. His posts are often deleted, but the account has remained operational.
"I care more about having an impact on society than holding exhibitions for academics," he said, contrasting himself with high-profile artist Ai Weiwei, who is rarely displayed in China.
"Many people in the West think that Ai Weiwei's work is great, but over here it's not shown," he said. "A lot of his thoughts cannot be exchanged with the masses."
Ultimately, though, Ou would prefer there was no need for him to bare his flesh.
"I hope that China will stop having the kinds of incidents which need my involvement," he added. "That way I can live quietly".