Marisa Parella stops sharply. Her toes hover just centimeters from the edge of the yoga mat.
She almost forgot to bow before starting Budokon class, a workout that fuses yoga with various martial arts, including karate, jiu-jitsu and tae kwon do.
Nearby, Juliana Bonilla was already on the mat at DC Aikido Dojo in Washington, bending down to touch her toes after pausing for a moment to adjust the white martial arts belt that is wound around her waist.
The white belt is the mark of a novice -- a teacher in training -- and most importantly for Bonilla, it means she is one step away from receiving an embroidered red belt that will give her teacher status.
"It's not just a workout you do for an hour," she said. "It's a lifestyle change. Budokon has allowed me to step back and look at things in my life."
With 43 percent more Americans currently practicing yoga than in 2002, according to the second annual "Yoga in America" survey collected by the Harris Interactive Service Bureau on behalf of Yoga Journal, the thirst for "yoga hybrids" like Budokon is also on the rise.
From disco yoga to yoga in the nude, gyms across the country are reshaping yoga to satisfy more than 16.5 million yoga enthusiasts nationwide, while simultaneously luring an American culture that pounces on fitness fads.
But, warns Dr. Cedric Bryant, chief science officer for the American Council on Exercise, while fitness hybrids encourage creativity and make exercise more appealing, some classes could strip yoga of its value.
"It's just trying to be innovative to attract an audience," Bryant said. "In the quest for making things new and different and innovative they will compromise some of the benefits."
Do Your Research
According to a 2005 American Council on Exercise study, yoga alone has significant physical benefits.
Thirty-four women who participated in the study increased their strength and flexibility significantly over an eight-week period.
However, if yoga is not enough for you, Bryant recommends looking for the following in a hybrid class:
Does the teacher have an extensive background in both arts that have been combined?
Did the teacher go through a certification program or programs approved by the council?
Has the hybrid received a lot of publicity?
Does the teacher's style mesh with my own yoga philosophy?
Does it work both the mind and body?
Are the fundamental yoga moves incorporated into the class?
Bryant said Budokon had a higher level of credibility because the founder, Cameron Shayne, had more than 20 years of training in the classical arts of yoga, martial arts and meditation, all of which Budokon intertwines.
"I think it has the potential to be viewed as a compliment to other martial arts forms and could have staying power," Shayne said, explaining that Budokon translates from Japanese to "Way of the Spiritual Warrior."
Karate Kid, Yoga Master
At the hourlong Budokon class in Washington, several students attempted to invert their body and hold it up using only their arms. Most fell, blaming their weak arm strength for their failure.
Instructor Mimi Rieger said it was not physical weakness, but fear that sometimes held students back.
"If you're not completely synchronized with your mind and body, it's hard," said Rieger, who teaches Budokon and yoga classes five nights a week.
After going through an intense series of yoga poses, ground fighting moves that require students to synchronize their hands and feet, and repetitive karate kicks and punches, Bonilla tried to invert her body once again.
This time, her movements were seamless.
"Do you trust you to be there for you when you're upside down?" Shayne said. "The minute you start thinking, 'Can't,' you're splitting the mind. You're not in the moment."
The only reason we suffer in the world, he says, is because we compare one moment to the other.
Like those who practice Budokon, the self-proclaimed "urban monks" at the One Taste Urban Retreat Center in San Francisco use traditional yoga to promote healthy balance between the mind and body.
The major difference -- some at One Taste practice their yoga in the nude.
"There's this freedom you feel when you can be around people naked that comes out in every part of your life," retreat resident Nicole Halpern said. "You see the human beings and realize that we are, at a fundamental level, all the same."
One Taste's founder, Nicole Daedone, introduced nude yoga to the community two years ago, after watching people practice it on a rooftop at the Harbin Hot Springs retreat center in California.
Daedone said about 10 new people a week came to her center to experience the "liberation" of nude yoga.
"After yoga, the people look really good," she said. "The people who have taken nude yoga look transcendent."
African Dance and Yoga
Despite all of the standard and hybrid yoga classes available, Angelique Shofar of Washington said she had found something missing from her daily yoga practice -- her African heritage.
Born and raised on the west coast of Africa, Shofar uses African dance and eclectic music to create a deeper, more personal connection between her mind, body and spirit.
She calls it SoulFul Yoga.
Her new students also get a yoga journal, which they use to declare their intentions, log their experiences, and share passages for support.
"It's just powerful when you document something," she said. "When you write it down, it helps manifest it faster."
For further inspiration, Shofar brings her 8-year-old son, Julian Shofar, to most of her classes.
Julian said yoga poses, like the cobra, had made him a better athlete. When Julian does the cobra, he said he lies on his stomach and coils upward toward the sky -- like a snake.
"When I play soccer, I use yoga to stretch my legs so I can kick better," he said.
Peggy Hall, creator of the "Yoga for Surfers" DVD series, says athletes can find a series of yoga poses to counteract the damage that their sport does to their body.
If you're a surfer, for example, you're going to want to open up the shoulders, neck, back and hips, which tighten from surfing.
"Yoga is an excellent tool to complement whatever activities you're involved in," Hall said. "It's one of the only sports that restores your energy."
No matter the hybrid, Shayne says that as long as a student fully engages in the practice, he or she can find value in it.
"If you are in a Zen state of mind, you can make digging a ditch the most incredible experience you've ever had," he said.
Phil DiPietro, owner of Yoga Mandali in New York City, says that even though he does not practice hybrid yoga, it is a valid way to draw out the yoga that exists in all of us.
"At the highest understanding all paths lead to the same place," DiPietro said.