How Yoga Can Wreck Your Body

See the url for the complete NYT article. Here is one paragraph, The
BMJ article has no abstract so ask your yoga teacher for it.
http://www.nytimes.com/2012/01/08/magazine/how-yoga-can-wreck-your-body.html?pagewanted=all
Be careful out there.
Clinicians recorded a number of similar cases and the condition even got its own name: “yoga foot drop.”

More troubling reports followed. In 1972 a prominent Oxford neurophysiologist, W. Ritchie Russell, published an article in The British Medical Journal arguing that, while rare, some yoga postures threatened to cause strokes even in relatively young, healthy people. Russell found that brain injuries arose not only from direct trauma to the head but also from quick movements or excessive extensions of the neck, such as occur in whiplash — or certain yoga poses. Normally, the neck can stretch backward 75 degrees, forward 40 degrees and sideways 45 degrees, and it can rotate on its axis about 50 degrees. Yoga practitioners typically move the vertebrae much farther. An intermediate student can easily turn his or her neck 90 degrees — nearly twice the normal rotation.