SAN FRANCISCO -- It's gone way beyond your neighborhood yoga studio. Google and Twitter offer yoga classes to employees. The Giants have Yoga Day at AT&T Park, inviting fans to practice their downward dog in center field before the game. There's also yoga on the South Lawn of the White House at the annual Easter Egg Roll.
About 20.4 million Americans practice yoga, according to a survey by Yoga Journal. With that boom in popularity has come an explosion of scholarship -- and an exhibit at the Asian Art Museum of San Francisco titled "Yoga: The Art of Transformation," which continues through May 25. It surveys yoga's 2,500-year history -- a quest for an enlightened mind and supple body that began among wandering Indian ascetics. It is billed as the first major art exhibition on yoga, and the Asian Art Museum is its only West Coast venue.
The exhibit debuted in October in Washington, D.C., at the Smithsonian Institution's Arthur M. Sackler Gallery.
"But it had to go to California," said Debra Diamond, the show's organizing curator, who flew out for the opening in San Francisco. "I think the percentage of people who do yoga and care deeply about yoga -- it's the place. Yoga and Indian culture are deeply embedded."
At the museum, the story is told through sculpture and painting, manuscripts and film. India's greatest artists have long grappled with yogic themes, it turns out, and the exhibit is a visual feast. It should appeal even to those who don't tote yoga mats along with their decaf lattes.
Watercolors are brushed with ground gold to shimmering effect. Sculptures of sages and divine figures have hips that appear to sway alluringly. One 13th-century figure drips with snakes that fool the eye; they look more like vines heavy with blossoms, intricately carved. And protruding from his lips are two deadly fangs.
"And just look at this beautiful bejeweled woman," said Qamar Adamjee, the Asian Art Museum's associate curator of South Asian art, during a preopening tour. She stood before an 11th-century sandstone figure that spells feminine power: "I love this sculpture. See the softness of the belly, and there's her voluptuous body, and yet she's holding a sword and a shield, and she has teeth," more typically associated with demons in Indian art.
This yogini -- part mortal, part goddess -- sits spread-legged on an owl and is about to take flight. Her pointer fingers are inserted into her mouth as she prepares to emit a war whistle. Historically, yoga has not been only about peace, you see; ancient Indian kings called upon yoginis -- embodiments of secret yogic powers -- to wage battle and expand their kingdoms, according to legend and belief.
Yes, yoga holds out the promise of individual transformation, whether through blissful enlightenment or a beautiful body. But yoga itself has transformed through history, with shifting emphases and meanings.
As today's practitioners bicker over yoga styles -- Iyengar versus Bikram or Ashtanga -- they re-enact a historic debate: "In modern yoga, there's a lot of criticism: 'Oh, this isn't authentic yoga,' " Kaitlin Quistgaard, former editor-in-chief of Yoga Journal and now an adviser to the exhibit, said in an interview. "So the exhibit is timely and fun in showing us that this isn't even our argument. This is a fight that's been going on for hundreds or even thousands of years, take your pick."
Yoga has moved across borders and religions. It is closely identified with Hinduism, but it has been adapted by Sufi Islam, Jainism and Buddhism. The exhibit's most ancient sculpture -- about 1,900 years old -- is Buddhist.
The first illustrated treatise of yoga postures dates to 1600-04, commissioned by a Muslim Indian emperor. Titled "Ocean of Life" and published in Persian, its pages stretch across a wall at the museum. In one image, a yogi performs a rock-solid headstand. In another, a yogi sits in lotus position. He is long-haired and bearded, and he looks something like Jesus -- probably not a coincidence, as the emperor's liberal court welcomed Jesuit missionaries.
The exhibit's 130 artifacts stretch into this century. A 1938 film of T. Krishnamacharya, sometimes called the "father of modern yoga," shows him gliding through pretzel-like poses. Eat your heart out, watching, if you do yoga.
In a clip from the 1941 movie "You're the One," a jazz singer performs with a big band while a goofy, mustachioed swami squats in front of a crystal ball. The tune has lyrics by Johnny Mercer:
There was a yogi who lost his willpower
He met a dancing girl and fell in love.
He couldn't concentrate or lie on broken glass.
He could only sit and wait for her to pass.
The film clip typifies the patronizing attitudes toward yoga that once were common in the West. But yoga, as the exhibit demonstrates, has had the last word, spreading to all corners of the planet. Recent permutations include yoga on the slack line (imagine headstands on a tightrope), aerial yoga (think flying trapeze) and acro-yoga (think acrobatics).
Friday's opening was capped by a concert and yoga class, each led by Marin-based rapper Nicholas Giacomini, aka MC Yogi. There were acrobats and dancers. Yoga was transforming once again, Giacomini said, allowing guests to "experience the exhibit and then come and dance and celebrate and feel how the tradition is alive, not just confined to framed pictures on the wall."
Through: May 25; 10 a.m.-5 p.m. Tuesday, Wednesday, Saturday and Sunday, 10 a.m.-9 p.m. Thursday
Where: Asian Art Museum of San Francisco, 200 Larkin St.
Tickets: $5-$17; 415-581-3500, www.asianart.org/yoga
Also: See details on related workshops, panel discussions, dance, music and family events at www.asianart.org/yoga