What does yoga look like in your mind's eye? Serene people joined in meditation, chanting "Ohm" in between impossibly pretzel-like poses?

If so, you might want to put that notion on hold. The ancient practice of yoga has some new variations that might have first-century yogi Patanjali rolling over in his grave (or in his current reincarnation) Since its meteoric rise in popularity in the Western world over the past 20 years, many forms of yoga have become trendy, including heated Bikram methods and fusion yoga that incorporates ballet or Pilates.

Check out some of these crazy new yoga styles:

Anti-Gravity Yoga

I was completely intrigued when I first heard of anti-gravity yoga earlier this year, and I couldn’t wait to try it. After its beginnings in the field of aerial acrobatics in 1990, the practice grew as a yoga fitness program in New York. There, Travis Shrader and his wife, Sarah, discovered the practice, which uses silk materials like the aerial artists in Cirque de Soleil employ.

"After taking just one class, we were hooked," Sarah says.

The silk creates a hammock that hangs suspended three feet off the ground; participants utilize this hammock to work muscle groups free from the compression of gravity. The realigning suspension of this type of yoga allows the practitioner to invert into upside-down poses and get into deeper stretches in a completely supported environment.

The Shraders became trained in anti-gravity yoga in New York and then decided to return to Texas.

"After moving back to Austin, we decided to bring it to Texas to spread our love for the technique," says Sarah.

When I tested it out, I agreed that it was a lot of fun while also providing a very challenging workout. Poses can be modified to accommodate each person, and the feeling of simply dangling in the air made me feel like a 5-year-old. Unfortunately, Austin's Fit to the Core is currently the only AntiGravity Yoga studio in Texas.

AcroYoga

This is also known as partner, synergy or contact yoga. It, too, draws inspiration from circus acrobatics — two people get into yoga poses together using balance, inversions, spotting and play. AcroYoga has elements of Thai massage and is meant to cultivate trust, connection and playfulness.

It all started in San Francisco in 2003. Jenny Sauer-Klein and Jason Nemer met at a party through mutual friends. Afterwards, they started doing some casual, playful contact yoga together — Jason held Jenny in a handstand on his hands, and Jenny supported Jason in a therapeutic flying sequence, which uses gravity to release the spine. It's inversion without the effort.

Their personal interactions laid the foundation for AcroYoga, and they started teaching a partner doubles class in San Francisco.

"When you are able to give and receive completely, it brings up what yoga is all about — union," Jenny told Yoga Journal in 2008. There are now 120 certified AcroYoga instructors around the world.

Through a website and Facebook group, AcroYoga devotees get together for classes and unofficial, playful partner yoga sessions that they call "jams."

"Formal classes and workshops taught by experienced instructors, in my opinion, are the best places to learn Acro skills," practitioner John Richter says. "Jams are a great place to practice what you've learned in the classes and connect with other people in the community.

"In this way, jams and classes have a synergistic relationship. AcroYoga is very much like social dancing. If you don't know how to dance, you take some lessons before you go to the social dance, so you can learn some moves to practice."

Naked Yoga

Yes, you read that right. There are actually groups that practice yoga in the nude (only open to those 18 years and older).

"Each of us has his own reasons for choosing to practice yoga naked," states the Naked Yoga website. "Some enjoy the greater physical freedom. Some of us want to feel more comfortable in our own skin. Some enjoy the taboo-breaking thrill of getting naked.

"Still others see nudity as a profound spiritual experience — a shedding of armor and barriers and the social masks we present to the world."

It might not come as a surprise that naked yoga devotees are mostly male. Many of its participants self identify as gay, but the groups are usually open to all. The FAQ on the Naked Yoga website is very informative and frank.

Is there ever sexual energy present? "Yes, sometimes, but it's okay to feel it without acting on it, and there is no sexual activity nor genital focus in the classes."

"But what happens if I get an erection?" some of you might ask, a la George on Seinfeld (remember the male masseuse episode?) The website answers: "Erections are natural and okay, but are not as common as you may think. In yoga, the mind and body are actively practicing yoga and most of your energy is going towards supporting the yoga practice, not an erection."

Naked Yoga seems to be more about feeling comfortable in your own skin and forgiving of your body. Houston classes are offered and coordinated via the group Facebook page.

"I starting coming to naked yoga to help get more related to my body," one participant says. "I’m learning to accept my body, imperfections and all, instead of hating it. And doing yoga is giving me the extra energy I need to take better care of my body.”