White Collar Boxing takes non-boxers - mostly white-collar professionals - and gives them the chance to punch each other for a cause. Photos by Fan Zhen / China Daily

A charity boxing competition for office professionals hones their fighting spirit inside and outside the ring. Eric Jou reports in Beijing.

The bell rings. Punches fly - first a jab. Then a hook. The bell sounds again, and the fight is over. It's finished in six minutes - six short minutes, following three long months of grueling training. But game designer Samuel Green says it was all worth it. Green removes his headgear and gloves, and pulls out his mouth guard. He receives a medal for the show he just put on. The decision is announced. The crowd rages. Green lost, despite a major comeback near the end of Round 2. But he isn't upset. Green didn't sign up for White Collar Boxing to win the competition. He did it to experience something new.

Standing 1.78 meters tall and weighing 74 kilograms, Green doesn't look like what most people expect of a boxer.

The video-game designer spends his days working on computers at a desk.

He had virtually no fighting experience before he signed up for White Collar Boxing.

"It's just a challenge," he says.

"It's something I've never done before. I like to get fit and test myself, and learn something new. I'm a game designer by profession. So I like getting into challenges and working out things. There are a lot of parallels between (video) games and sports."

White Collar Boxing has only recently arrived in Beijing since it started in the United States. The competition has been staged annually since 2008.

It essentially takes non-boxers - mostly white-collar professionals - and gives them the chance to punch each other for a cause.