Suspended from the ceiling in fabric hammocks, six yoga students sway slightly, snug and relaxed in their red and blue pods.

"Let yourself hang," teacher Becky Stella reminds the aerial yoga class. "Let your belly release. Soften at the knees; swing side to side in unison with your breath."

It's twilight at the Yoga Center of Minneapolis, where Stella teaches what she believes is the only aerial yoga class in Minnesota, and possibly the Midwest.

Using the hammocks as a tool, participants lunge and stretch into positions more easily than they could on the floor. The benefits of the weightless poses: strengthening the core, stretching muscles, helping heal injuries and relaxation.

But how easy can it really be to look graceful and find your inner peace when you're dangling from a rope in a piece of fabric?

"It feels like, 'Omigod, I'm going to fall!' but you're not," Stella assured as the class moved into a forward fold and swung upside down. The participants in this class are veterans; Stella encourages newcomers to ease into inversions, gradually increasing upside-down time. Sometimes, the blood rush results in uncontrolled laughter.

"It took me awhile to get used to hanging upside down and to really trust the sling and let go," said John Koivisto. "The longer I do it, the easier it gets to focus on your breath and relax."

Classmate Katherine Schlaefer dropped into an upside-down lotus position, enjoying the stretch for several minutes. She started aerial yoga while recovering from a long string of injuries, and found it to be both restorative and complementary to her triathlon training.

"Practicing poses and playing off the ground changes your relationship with gravity," she said. "Working in multiple dimensions ... develops strength in both core and stabilizing muscles and hones body awareness and spatial perception. This seems to translate to greater efficiency and fluidity in swimming, biking and running."

Stella discovered aerial yoga when her interests in yoga and aerial acrobatics made her wonder if anyone had thought of combining them.

They had: A Google search led her to Michelle Dortignac's Unnata Yoga in New York, and Stella was quickly selected to join her first teacher training workshop two years ago.

"The curriculum is really beautiful and well thought-out," Stella said. "But the main point of the training, she says, is that in every class we should ask, "What is the point? Why are we doing this?"

The answer, Dortignac hopes, is that it's not a trendy spinoff that loses sight of the traditional yogic principles of connecting the right and left sides of the body and bringing the body into union with the mind.

Dortignac and Stella think of the hammock as a tool. Like Stella, Dortignac was already doing yoga when she started taking aerial acrobatics classes for fun.

"I could feel the places where it was easier, like getting into back bends, when you're supported in the air," she said. "It made me think that [the hammocks] could be the missing links in floor yoga practice in terms of full-body health and fitness. I had the thought that this could be a great tool to use."

The idea wasn't totally new: Slings were already being marketed as tools, but Dortignac took that a step further by developing whole classes around the hammock.

Larger corporations have gotten in on the act, too: AntiGravity Yoga has franchises scattered around the United States, Great Britain and Europe, although none in the Midwest. Stella and Dortignac are both more interested in developing the technique than promoting it.

"It kind of evolved organically," Stella said. "I didn't do a lot of promotion. ... A lot of people have actually found it [on their own], and we've gotten good, steady traffic. People who really like it stick with it."

Koivisto learned about aerial yoga from another yoga teacher who thought it might help loosen areas tight from injury. His doctor agreed, so he signed up. Now, he says, he's more flexible, has better coordination and balance, and sleeps better.

"The results for me were kind of subtle at first, but now I have been experiencing some good release," he said.

There's another obvious benefit, participants say: fun.

As Schlaefer and Katie Adducci worked on a new pose, making Superman-like capes around their shoulders and flipping into a resting position for shavasana, or resting pose, that playful element is clear.

"This is my favorite part," said Adducci, who worked with aerial silks as part of a children's show in college, and was thrilled to find a way back into her unique hobby.

Sometimes students can't stop laughing at the craziness and euphoria of being upside down, said Stella, adding that it brings back memories of childhood.

"I like the feeling of being upside down, and this has been a journey getting back into that," she said. "Now I feel like I could be upside down half the day."

For Stella and Dortignac, however, aerial yoga does not replace traditional floor yoga.

"I always relate hammock work to a vitamin supplement," Dortignac said. "I wouldn't want to live off it, but it really helps push you further, faster."

Sheila Mulrooney Eldred is a Twin Cities freelance writer