Another member of Uppercut, Wang Yifan, says she enjoys squaring off one-on-one with her boxing coach, an interactive session which distinguishes boxing from other, self-managed fitness activities like running.

"I didn't really enjoy boxing, because I wasn't good at first, but when I found the rhythm and power, everything changed," Wang says. "I enjoy the clean and powerful sound of fists hitting the target held by the coach. It's like music to my ears."

The interaction between boxing classmates has also made Wang many good friends. Last year, she and several of her fellow pugilists even participated in the Spartan Race together, spending a day crawling through mud and climbing obstacles together.

"I think boxing is like opening the door to a brand-new world, bringing more possibilities to my life. Whether it's shaping up, meeting new friends or facing challenges with more confidence, it makes me better," she says.

Other benefits of boxing, especially for women, may be the boost to their self-confidence and the way it helps them cultivate a strong mentality.

Tatiana Coverson, born in Colombia, has been in Beijing for over two years. Since 2018, she has been riding her bicycle for 15 minutes a day to take boxing lessons with her Filipino coach at Train Yard, a regular gym in Chaoyang district.

Describing herself as a young woman who is interested in "aggressive" sports, the 22-year-old says that when she discovered boxing it was like "falling in love at first sight".