A couple of months ago, Marguerite Nozaki, a 27-year-old lawyer, was looking for a way to relieve stress after work.

Tired of cardio machines at the gym, she decided to take up boxing, a sport she had discovered several years earlier.

Though she was just looking for an outlet after a long day at work, Nozaki discovered the physical and mental benefits from the twice-weekly workouts at Kalakaua District Park gym.

"I feel like I can defend myself and I have a lot more self-confidence," said Nozaki, putting on her yellow handwraps one Tuesday evening at the busy gym. "And I'm working out parts of my body I didn't know I had."

Boxing — in all its forms — continues to be a growing trend in the fitness world, according to the American Council on Exercise, thanks to people seeking non-traditional, out-of-the-gym workouts. It's become so popular that nearly a quarter of all health clubs in the United States offer some sort of boxing-related class.

At Kalakaua District Park on a recent Tuesday evening, more than 50 people packed the boxing gym, some hitting the hanging punching bags, others sparring in the two rings. Twice a week instructors hold free classes to teach first-timers the basics and proper technique.

With the growing popularity of mixed martial arts and an interest by people to get fit out of the gym, boxing clubs in Hawai'i are seeing an increase in participation.

And these participants are getting an intense workout.

"It's a total-body workout," said Bruce Kawano, one-time professional fighter and USA Boxing Hawai'i Junior Olympic chairman. "You're working your upper body, you're moving around, you're using the jump rope. So you're building stamina while toning (your muscles)."

One of the biggest concerns people have about boxing is major injury, particularly to the head, Kawano said.

While professional boxing has taken blows by critics — some groups are even calling for a complete ban on the sport — amateur boxing, with its use of protective gear, has proven to be safer than its pro counterpart.

According to USA Boxing, amateur boxing ranked 23rd on the National Safety Council's list of sports-related injuries, behind hockey, soccer, gymnastics and inline skating.

"People think boxing is about punching people in the face or that it's violent," Kawano said. "But it's not like that."

Ron Richardson, 55, has been boxing since he was 6 years old, learning from his dad at Kalakaua District Park.

The former competitive boxer still holds his own at the gym, sparring with — and beating — guys half his age.

"Boxing instills in me self-confidence and humility," said Richardson, a police officer from Kailua who trains four times a week at the gym. "You learn what your body can do and you improve your balance, coordination and agility ... It keeps me young."

He's broken his nose twice and his thumbs three times. But despite the injuries, Richardson said there's no better workout than boxing.

"This is the juice here," Richardson said, smiling. "And I gotta get a squeeze."

WHERE TO LEARN

Kalakaua Boxing Club: Held at Kalakaua District Park gym, this club offers free recreational boxing for youth and adults. Free lessons are 9:30 to 11:30 a.m. Tuesday and Thursday for adults; 3:30 to 5:30 p.m. Monday through Friday for children. Open boxing times are noon to 6 p.m. Monday, Wednesday and Friday; 9:30 a.m. to 6 p.m. Tuesday and Thursday; closed Saturday, Sunday and holidays. 720 McNeil St. 832-7801.

Palolo Boxing Club: Part of USA Boxing and the Police Athletic League, this club focuses on both recreational and competitive boxing. Group training classes are from 4:30 to 6:30 p.m. Monday, Wednesday and Friday. Individual classes available by appointment. Cost is $25 a month, youth (age 8 to 16) are $15. Most equipment is provided or available for purchase. Palolo District Park, 2007 Palolo Road 733-7358, paloloboxingclub@yahoo.com.

PearlSide Boxing: This school offers beginner and advanced classes for youth and adults. The beginner (or fitness) class is held 6 to 7 p.m. Tuesday and Thursday; the advanced class runs from 7 to 8:30 p.m. Tuesday and Thursday. Cost ranges from $50 to $70 a month. Momilani Community Center, 715 Ho'omoana St. in Pearl City. 256-2885, www.pearlsideboxing.org.

WHAT YOU NEED

Handwraps: These wraps help protect the bones and tendons in your hands from injury when you're hitting the punching bag or sparring with a partner. They also provide support for your wrists and thumbs. There are various kinds of handwraps. The most popular in gyms are Mexican-style handwraps, which are made with an elastic material that contours to the shape of your hand. Cost is about $8 to $10.

Training gloves: Leather gloves, which are pricier, are recommended because they'll last longer and provide better support. And opt for Velcro straps, which are easier to get on and off than lace-up gloves. Cost is around $40.

Jump rope: Nearly every boxer uses a jump rope for training purposes. Cost ranges from $5 to $15, depending on quality.

Protective gear: Beginners may not need this at first, but later you'll likely need a headgear, mouthguard and body protector.