Summer days bouncing on a trampoline in the backyard were once the embodiment of carefree fun. The wind blew through your hair and the smile never left your face—maybe you even attempted a few flips. Safety concerns have made trampolines less ubiquitous, but you can still relive those halcyon days and get a heart-pumping workout at the same time on a mini personal trampoline.

It’s called urban rebounding and although it may look like a fluffy good time it’s considered one of the best low-impact aerobic options by fitness experts like Corinne Brown, owner of Fitness Incentive in Babylon Village. The cult-favorite gym began offering rebounding in 1991 and it immediately became a hit.

I’ve taken some rebounding classes (had to swallow my fear of looking like a klutz) and quickly got a handle on the choreography and movements, which are variations of a few basic jump types, all performed on a small, individual-sized rebounder. Almost anyone can master them in a class or two. A rebounder is usually about 40 inches in diameter, much smaller than a 14-foot wide trampoline, and designed as a piece of exercise equipment, not a recreational toy.

It’s been years since my last rebounding class so I was curious how it would feel after a long hiatus. I showed up for a half-hour class with instructor Kelly Wallace. The class was, in a word, fun. I had forgotten the free feeling of jumping to fast-paced pop songs and the great cardio burn achieved by dialing up the intensity. Many first-timers try to bounce on the rebounders like they are actual trampolines, but to get the maximum benefit, keep your bounces short and tight and use the resistance of the rebounder. If you float up into space and land three beats behind the rest of the class, you’re doing it wrong.

Kelly kept the class moving quickly. We spent a lot of time jogging in place on the rebounder, interspersed with intervals of faster pickups. Just like any good group exercise, the energy of the class was invigorating and inspired me to push harder. Actually the classes are suitable for any fitness level because “a good instructor can lead all levels, all ages,” Corinne said.

Most of the class was made up of experienced bouncers. 20 women and a lone brave man stayed in sync through some classic Jane Fonda moves like jumping jacks, kicks and a few isometric power moves. By slightly tweaking how we jumped, we recruited different muscle groups. At one point Kelly had us jumping extra high, tucking our legs under. As we flew up and down it seemed the point was simply to have fun and experience the childlike abandon.

I almost forgot I was working out, except of course for the sweating and heavy breathing. “It’s like running without impact and it’s easy on the joints. It’s not a fad. It never loses appeal,” Corinne says.

At Gold’s Gym in Smithtown, the regular attendees of Tracy Colavecchio’s 9:30am “Body Blast” class weren’t as enthralled with the rebounders. When Tracy announced the cardio portion would be rebounding, there was a collective groan.

Tracy sometimes uses a step or floor work to get heart rates up in between strength conditioning work. Requiring the all-female attendees to get up and bounce demanded more effort. “It’s just a resistance to something new. The rebounders force you to work and your heart rate really gets up.”

Tracy kept the routines very simple: She started slowly and built up to a moderate intensity but the class never really hit an advanced or hardcore tempo—good for a jumping newbie. “I want to get them to like it and not have the moves be so intimidating that people are turned off,” Tracy said.

There are always modifications for every move. If you’re feeling bored, jump harder. If your heart rate is skyrocketing, remove the arm work or bounce in place to regain composure. We did some sprints on the rebounders and intervals of full bodywork with weights. The class seemed to warm to the rebounders after a while. Who can stay grumpy while bouncing around to Beyoncé?

“The rebounder should be a playground,” said Gold’s manager Sue Slack. “You need to let go and have fun. The rebounder is here to stay in fitness.” And, if all else fails, as Tracy joked, rebounding is the perfect opportunity to test out the mettle of your sports bra along with your cardio chops.