A growing number of health clubs around the world offer exercise that allows people to stretch and strengthen their bodies while hanging in the air, often upside down. It is called AntiGravity Yoga.

The image of students hanging upside down on hammocks made of silk cloth connected to the ceiling looks more like acrobatics than yoga. Marie Bice is a student of Antigravity Yoga.

“When I first saw people hanging upside down from hammocks and calling it yoga I thought they were crazy. But it ended up being a lot of fun and just swinging it felt very playful.”

Ms. Bice says AntiGravity Yoga is not all play. It is also hard work, with benefits. “I don’t have a lot of flexibility in my back and doing this work has really helped my back with that.”

Instructor Heather Blair says hanging upside down helps the body in a way that regular yoga does not offer. “You actually have spinal decompression so when you’re upside down your vertebrae actually open up so the space in between the vertebrae opens naturally and gently.”

Ms. Blair says when Belief Fitness Studio first started offering AntiGravity classes over a year ago, people became interested very quickly. “You literally can be of any fitness level. You can have injuries. It doesn’t matter how old you are -- anyone can take the class. So it’s been a huge draw for us.”

AntiGravity Yoga creator Christopher Harrison is a dancer, choreographer and gymnast. "I created it so even my mother can do it.

Mr. Harrison first created this form of yoga for athletes. He made some changes and started teaching it to the public in the United States in two thousand nine. Since then, it has gained international attention. Several countries, including China, Indonesia, Russia and Brazil, now offer AntiGravity Yoga classes.

“AntiGravity Yoga is a combination of pilates, a little bit of yoga, aerial arts and suspension training so it’s not just yoga.” The fusion of stretch and strengthening exercises allows students to achieve movements that traditional yoga does not have. They include flying while suspended on the hammock and using the hammock to hang like a bat.

It is also more of a cardio-vascular workout than first time student Chris Meierhans expected. “I had no idea that it was that much work.”

But creator Christopher Harrison says the yoga philosophy is still at the core of this workout. “You can expect still to be studying yoga because it is a practice of awareness, of body, mind and spirit.”

Like traditional yoga, each class ends with meditation. But in AntiGravity Yoga, meditating means resting in the air while cocooned in a hammock.