There was a controversial article among the yoga community that came out in the New York Times Magazine last week, titled How Yoga Can Wreck Your Body. Before you get scared and swear off yoga forever, if you remember this one thing you will be just fine: LISTEN TO YOUR BODY. Any physical activity can cause injury (as can crossing the street, for that matter!) -- the key is being mindful in your practice. Yoga is not about competing with other students, contorting yourself just to please your teacher or proving to yourself that you are, in fact, the pretzel you are envisioning in your head on a day where your body just doesn't want to go there.Only you can know how you are feeling. If something doesn't feel right, stop and move into down-dog or child's pose. (That said, sometimes it can be good to push through perceived blocks or challenges -- but there's a big difference between that and pain that is about to cause bodily injury).
Pain is an information system. Consider my teacher, Ganga White's principle about "Surfing the Edges." In his book Yoga Beyond Belief Ganga describes how we all have edges of strenth, flexibility, balance, endurance, fear and pain. "Every yoga posture has different levels and intensities of engagement, and every body has its own limits. You can learn to adjust and modulate these levels by 'surfing the edges' to get different effects and benefits."
During your practice, you do not need to pushevery edge every time . . . or any time! Sometimes you will only go to 60% of an edge. Sometimes you will go to 80% and pull back. Or you'll breathe into a pose and realize you have room to deepen or experiment further. Do what feels right, and know the difference between a good stretch or challenging pose versus one that is actively causing pain. Ganga puts it really well when he says, "Each time you begin your practice, pay particular attention to where your edges are that day. Edges are on the move constantly, day to day and breath to breath. Every day you have a different body."