NEW YORK - Trampolining, said to have begun when Eskimos bounced each other on walrus skins for the fun of it, is putting a feel-good cardiovascular spring into group fitness classes, from body sculpting to dance, fitness experts say.
Also known as rebounding, it delivers a low-impact, calorie-burning workout that swaps the tedium of a treadmill or step class for a feeling of child-like euphoria.
At Chelsea Piers Connecticut, an adult fitness class twins trampolining with rock climbing.
"I wanted to do something fun. Everybody likes to climb as kids, everybody loves the bounce of the trampoline," said Byron Knox, a director and instructor at the Stamford-based facility.
No stranger to odd fitness combinations, Knox, who also coaches football and gymnastics, said the hybrid class works well.
"The trampoline is predominantly leg-based, although we do core exercises on it. The rock climbing is predominantly upper body, although you do use your legs," he said.
Knox compared it to working a leg press followed by using upper body equipment, but said it is more entertaining.
"Most people wouldn't think of trampoline as a workout but it takes a lot of energy," he said. "It could be equal (in cardiovascular intensity) to jumping rope. And part of the beauty is that the exerciser is in control."
The more flexible can jump and split-jump higher, but Knox said just about anybody can participate, and trampolining also enhances balance and spatial awareness.
At Chelsea Piers Connecticut the "tramp" precedes the rock wall.
"That part takes a bit more coaxing," Knox admits, although everyone is harnessed and spotted.
At JumpLife studio in New York City, some 25 mini-trampolines connect with low lights and top 100 songs to draw out the inner dancer.
"JumpDance is our signature class," said founder and CEO Montserrat Markou, of the 45-minute non-stop cardio workout, which she said can burn up to 600 calories.
She said the class doubles as a venue for bachelorette parties and girls' nights out.
"The low lights make people less self-conscious," Markou said.
Another class, called JumpGym, ditches the dance club vibe and incorporates weights and push-ups into the trampoline workout.
"JumpGym attracts more men," said Markou, whose mini-trampolines are equipped with a handlebar that can be grabbed should balance fail.
"People can work out who couldn't work out before," said Markou, who hopes to draw in seniors and children.
Rebounding classes at Crunch fitness centers pair mini-trampolines with sculpt, Pilates and interval classes. Group fitness manager Carol Johnson likens the bouncing motion to getting a massage.
"It's a bit more gentle on the body, more rehabilitative," said Johnson, who's been rebounding for about 10 years.
Jessica Matthews, an exercise physiologist with the American Council on Exercise, said trampolining is a joint-friendly way to add the cardiovascular component to a group fitness workout.
The intensity, she said, can vary from a brisk walk to a run.
She said the National Aeronautics and Space Administration has used trampolines to build bone density in astronauts.
Matthews cautions that while the impact is low, the surface of a trampoline is still unstable and cautioned that people who have lower-extremity instability must be aware of this.
She said people also combine it with other activities.
"Some do it while watching TV," she added.