What would you do for a great cause? Would you go through three months of grueling boxing training while juggling your day job and climb into the ring in front of hundreds of your friends and coworkers?

That’s what 16 amateur fighters did for “Executive Fight Night,” a semiannual Vegas-style boxing event designed to be an opportunity for business executives in Tokyo to let off some steam and raise funds for charity.

Participants went through 12 intense weeks with professional trainers to prepare themselves physically and mentally for the event. Organizers said the fighters were chosen based on skill level, weight and availability, from 40 people who tried out.

Adding to the pro boxing-style pageantry of the event, the fighters adopted nicknames in the style of seasoned pugilists.

“I felt the opportunity to get fit, to challenge myself to do something I’d never done before — boxing — to contribute to my community . . . It was a no brainer,” said 42-year-old David “Big Bad” Booker from the United States, executive director at financial consultancy Options Group Japan.

Training sessions were held either in the early morning or at night to accommodate participants’ busy work schedules, with many also doing additional training.

“Waking up at 5:30 (a.m.) twice a week, not drinking, dieting . . . I made a pretty drastic change in my body chemistry,” Booker said. “I lost 10 kilograms without really trying.”

Inspired by similar gala events in other Asian cities such as Singapore, Executive Fight Night was established in 2012 by Ginja Ninja Promotions, a group of expatriate workers in Japan.

As cofounder Eddie Nixon, who is also Adidas Japan K.K. vice president of group retail, put it: “We wanted to bring a spectacular event to Tokyo and we wanted to raise money and give back to Japan-based charities.”

The fourth and latest fight night was held on May 23 in the Grand Hyatt Ballroom in Tokyo’s Roppongi district, where spectators wined and dined as their friends and coworkers fought it out in the ring.

Adam “The Landlord” German, a 33-year-old Canadian general manager at Real Estate Japan K.K., said he found out about EFN two years ago from a friend. This was his second time in the ring after fighting in EFN2.

“I liked what it was about,” he said, “taking guys out of the bar and into the gym, raising money for charity.”

He said his wife and two daughters were not exactly thrilled when he told them he would be taking part in EFN2.

“They thought I was crazy. But I wanted to show the kids this is mind over matter, you just set your mind to it and you’ll do anything you want.”

Elizabeth “Hot Hands” Taylor from England, a former Virgin Atlantic Airways in-flight service manager and a fighter in the only women’s match of the night, said the eldest of her three sons told her, “‘Mummy, girls don’t do boxing!'” After a while, though, the children loved it, she said.

Of course, EFN is not just about relieving stress and achieving physical fitness. The charity aspect is a big draw for many of the fighters and spectators.

Over ¥6 million in proceeds from the gala event will go to Shine On! Kids, an organization devoted to bettering the lives of children in Japan who are battling cancer.

The charity group’s dog program sends teams of nurses and specially trained dogs to children’s cancer wards to provide emotional support to the patients and their families.

Shine On! Kids marketing manager Joy Fajardo said EFN and the nonprofit organization are a perfect fit. And she should know, as Fajardo fought in and won the first match of the inaugural EFN in November 2012.

“The message of Shine On! Kids is definitely about the fight,” Fajardo said.

While numerous organizations are committed to finding a cure for cancer, she said Shine On! Kids focuses on “individuals and the stories that are taking place right now and the lives that are being affected.”

EFN provides crucial funds to charities like Shine On! Kids, which is funded solely by donations. EFN has in the past also worked with the Run For The Cure Foundation, a breast cancer charity, as well as Refugees International Japan.

For last month’s EFN4, fighters paired up with children battling cancer, boosting their motivation to do their best in the ring.

“It’s a great cause, it’s a great event,” said 28-year-old participants Filip “The Boy” Pusnik, who is from Wales.