Go ahead and bang a drum, hang from the curtains and spin that hula hoop. Area gym instructors say it's good for you, even if you don't realize it.

The unconventional workouts are part of a movement to keep the masses focused on their fitness by disguising exercise as playtime, like spinach in brownies. And while more conventional spin, yoga and Latin dance-inspired Zumba aerobics classes remain gym staples, the quirky and even slightly juvenile additions have been attracting regulars.

"It sounded fun. It didn't seem like exercise," said 14-year-old Tyree Roberts about why he tested out a new class at Universal Fitness in Overlea that involved banging, drum-style, on a large exercise ball.

He'd come with his family to the gym, and each chose a class from a sign that they'd noticed on their drive from their Perry Hall home to Baltimore. Tyree was attracted to "Drums Alive," brought to the area from Germany by the gym owner and instructor, Patrick Leonard.

To a musical backdrop, Leonard barks out steps on where and when to hit the drums, as well as on dance moves and yoga stretches. He says it's appropriate for all ages, and on this day, Tyree was banging next to 63-year-old Pat Hodges, who said she was enjoying the mental "left brain-right brain" exercise that was good "for someone my age."

Tyree's grandmother, Gloria May, was checking out the class, too. Her granddaughter, Tiara Hurte, was next door in Zumba.

Gym operators are learning to balance the "tried-and-true" workouts that have kept their customers happy for years or decades with alternatives to attract people with different tastes, including those like Tyree and Hodges who may not normally go to a gym, said Meredith Poppler, a spokeswoman the International Health, Racquet & Sportsclub Association, a trade group.

With 120 million people worldwide now using 133,500 gyms, there are a lot of different interests, but also a lot of ideas for sharing, Poppler said. In 2011, the association reports there are more age-appropriate offerings for aging baby boomers, increasingly sedentary youngsters and active Gen-Xers.

The gyms also are adding training session for outside activities such as rock climbing and marathons and niche activities such as boxing. They are more personal trainers and wellness programs on nutrition. Instructors are again using hula hoops and other throwback equipment such as kettlebells. Also popular now are vibration and human-powered equipment.

Group classes of all kinds are growing in popularity. Gaining the biggest followings have been cardio-kickboxing, yoga, high-impact aerobics and dance style, and strength-training classes, the association said.

Dawn Moore-Guinness brought her Charm City Hoops classes to Meadow Mill Athletic Club in Woodberry and says they are a mix of aerobics and dance. Students must keep moving to keep the hoops going — and the calories burning at a rate of about 600 to 800 an hour, she said.

"People like it," she said. "You can get videos at Target, and there are a lot of others teaching it now. It's a great workout. It's gone a little mainstream."

Moore-Guinness is a trained nurse and part of a circus-style performance group that uses streams of fabric hanging from the ceiling, which has led to another class called aerial dancing and stretching. Fellow performer Robin Miller brought this class to Meadow Mill.

She said she found the performances were a good workout and thought she could teach others.

On a recent day, Hillary Dempster, 25, and Alise Reneau, 24, were wrapping their feet in material and shimmying up to the ceiling like most people did on that rope in gym class as kids

"There's nothing like lifting your whole body to make you stronger," said Dempster, who is also using the classes to conquer her fear of heights.

One recent revening, Shanita Starks was watching the climbing across the room but was concentrating on the hoops. It was the first class for the 37-year-old Hamilton resident, though she had discovered the 1950s-era Wham-O Hula Hoop at a festival two years ago and now owns 15. She attributes her loss of 60 pounds to the aerobic exercise she gets from them, as well as yoga and walking.

The class lured her to the gym.

"This is so joyful," she said. "If you're having a bad day, get out the hoop."