Garrett Brick (in blue), 26, of Canada fights with 31-year-old American Toby Jarman. [Photo by Jiang Wanjuan/chinadaily.com.cn]

Boxing also trains fighters to discover their limits and strength, and to look for a strategy that works best for them.

"I've got a very strong right hand, and I move well," said Shan. "My weakness is that I don't read my opponent very well, and I can get nervous sometimes".

Himle shares the feeling when facing an opponent in the ring. “There is no other sport that people are coming at you, and you are the target," she said. "So you need to train your brain just as much as you need to train your body".

"Whether you feel scared or not, when someone throws a punch on you, you forget everything you've learnt," said Brick, "You have to train yourself to do something smarter, that's the sort of development you can take to other parts of your life".

After all the preparation the 16 fighters contested 8 bouts, three rounds of two minutes each, at the Park Hyatt Hotel in Beijing during a black-tie charity dinner attended by around 500.

"There is no other feeling in the world like going into the ring and having your family and friends cheering for you," said Himle. "It gives people a dream to live outside the office".