The Atlantic has the story:
Thick, glossy copies of LA Yoga, Yoga Journal, and Yoga Magazine cover the rickety folding table in the lobby of Green Tree Yoga and Meditation. The magazines share tales from Malibu, Santa Monica, and Pasadena. Nearly every spread features a thin woman, usually in slim yoga pants and a tight tank, stretching her arms toward the sky or closing her eyes in meditation. Nearly all of these women are white.
But in South Los Angeles, where Green Tree opened last year, fewer than one percent of residents look like the people in those pictures.
“You can look at all those journals and you'll not see one woman of color,” said Raja Michelle, herself a white woman, who founded the studio. “We associate yoga with being skinny, white, and even upper class.”
“You go to classes and you’re the only black person, or there are very few,” said Robin Rollan, who practices yoga in New York and D.C. and runs the popular blog Black Yogis. “People who find my blog say, ‘I thought I was the only one.’”