Cui Deyi, known as "Polar Bear," plays mahjong while standing waist-deep in a box filled with ice in Handan, in China's Hebei province on January 16, 2016
Buried waist deep in ice for more than an hour wearing nothing but a pair of swimming shorts, the man known in China as "Polar Bear" shivered and laughed at the challenge.
"At the moment I feel very good," said Cui Deyi, his torso exposed to near-freezing winter temperatures in the northern Chinese city of Handan on Saturday.
Cui is one of an elite group of global competitors testing humanity's ability to withstand extreme cold.
"I could continue at least another hour," said Cui, with the steely confidence of a man who reportedly submerged for seventy-five minutes in near-freezing waters off the coast of Norway in 2011.
With fragments of ice pressing against his lower body, the rotund athlete's arms were rocked by shivers. But that did not prevent him from winning several games of Chinese chess.
At rapid fire speed he slammed pieces down on a board in front of his transparent tub, securing victory against a local opponent.
"I'm using chess to test my ability to withstand cold, and to see if my thoughts and hand reactions are suffering," he added, still half-submerged.
Cui hails from Huangshan in the eastern province of Anhui, and began competing in cold endurance contests around a decade ago, after years of swimming in rivers and lakes during winter.
"Other people would shiver a lot after five minutes or so. But I could do half an hour on an hour with no problems," Cui said.
"So I slowly started to turn it into a profession".
-'I'll take them on'-
Winter swimming, which sees enthusiasts breaking into iced-up waterways for dips said to stave off illness, is popular in many parts of China, and even has government backing.
There are several hundred Chinese clubs dedicated to the hobby -- including one in Handan which organised Cui's challenge, beside a half frozen lake named Yiquan.
A crowd including several government officials surrounded Cui, beside a large red sign reading "freely swim in Yiquan lake and build the China Dream".
Local Winter swimming enthusiasts said their endurance paled before the man known as the "Polar Bear of Huangshan".
"We can't be compared to him, he's great... Ordinary people can only look on with respect" said Wu Guangji, 50, donning a yellow swimming cap in preparation for a plunge.
Cui is not the only cold-endurance competitor in China. In 2013 he faced off against challenger Jin Songhao, with both submerged up to neck-level in ice tanks.
He emerged victorious after 138 minutes, reports said. He has since claimed victories against Russian competitors.
Internationally his biggest rival is Dutch national Wim Hof, known as "Iceman".
He managed to set a world record by reaching 7,400 metres (24,278 feet) on Everest in 2011 wearing just a pair of shorts.
Hof insists that he has no special powers, and depends on decades of training in meditation and yoga.
But Cui challenged the Dutchman, saying: "Whoever in the world is good, I'll take them on, and see whose body can withstand more".
Minutes later he was pulled out of the ice tank, with assistants quickly handing him a white bath robe to cover his black swimming trunks.
The outside temperature was a bracing two degrees celsius (36 Farenheit).
After being patted down by assistants trying to restore blood circulation to his icy-cold extremities, he dressed and retired to a hotel.
Warming up over a bowl of noodles and vegetable dumplings, he said he relied merely on regular practice -- including half an hour a day sleeping in an ice bath.
Referring to his abilities and daily regimen, he asked simply: "It's pretty awesome, isn't it?"