Yoga's meteoric rise in popularity means that, inevitably, some people would start abusing its benefits. In a new profile by the New York Times, writer William J. Broad covers the dirty side of yoga, beyond all the "ohms" and new-age health benefits. Broad speaks to Glenn Black, a dedicated yogi with over forty years of teaching experience. Despite his commitment to the discipline, an incident in 2007 where his back gave way while he was using yoga to rehabilitate a ruptured disk in his spine, caused him to reassess his beliefs. He also recalls witnessing a yogi in India break three ribs while doing a spinal twist and a woman who had a stroke from hyperextending her neck. Black continues to teach a different kind of free-form yoga—one that doesn’t teach traditional poses and emphasizes awareness of your thresholds rather than putting the pressure on to achieve poses. He goes so far as to say that most people should stop doing yoga altogether. "Yoga is for people in good physical condition. Or it can be used therapeutically. It’s controversial to say, but it really shouldn’t be used for a general class." He also adds that each class needs to be tailored to an individual's needs and weaknesses. "To come to New York and do a class with people who have many problems and say, ‘O.K., we’re going to do this sequence of poses today’—it just doesn’t work." "Today many schools of yoga are just about pushing people,” Black cautions. "You can’t believe what’s going on—teachers jumping on people, pushing and pulling and saying, ‘You should be able to do this by now.’ It has to do with their egos." Still, the number of people who are dedicated to yoga outweighs people like Black. At a conference, Black tried to argue his case against the practice. "My message was that ‘Asana is not a panacea or a cure-all. In fact, if you do it with ego or obsession, you’ll end up causing problems.’ A lot of people don’t like to hear that."