William Broad, a New York Times science writer, has a lot of nice things to say about yoga. There’s good reason, he says, that this mix of stretching, bending and deep breathing, with roots in ancient Indian meditation, has attracted as many as 20 million Americans. Greenville Yoga
He also has some bad things to say, and he said many of them in a recent story titled “How Yoga Can Wreck Your Body.” It focused on yoga’s “potential to inflict blinding pain,” and it caused a lot of online outrage among dedicated yogis.
But the piece was an excerpt from a book out this week with the more even-handed title The Science of Yoga: The Risks and Rewards. And the author is no yoga-hater: Broad has practiced it since 1970 and just spent five years researching it.
His conclusion, conveyed in a phone interview: “There’s a lot of good stuff in yoga, but there’s also a lot of hype.”
How to choose a yoga class, teacher
There’s no scientific formula for choosing a safe, appropriate yoga class. Different branches of yoga have different criteria for teacher training, individual teachers and classes vary — and so do student needs and goals. But you can:
Ask about teacher credentials. Many will have a certificate showing 200 or 500 hours of training. Others will have several years of training, required by some yoga groups.
Ask if you can watch a class or attend a trial class before committing.
Be especially wary if an instructor adjusts your position without your permission or urges you to do anything that hurts, says Christina Geithner, a yoga teacher who is a fellow of the American College of Sports Medicine and a professor of human physiology at Gonzaga University, Spokane, Wash.
The good (and bad) stuff is revealed in studies Broad unearthed and in new ones published nearly every week. And the hype is evident in marketing behind all those yoga pants, snacks, videos and classes that have spread to nearly every cruise ship, senior center and YMCA across the land.
Science has yet to show what, if anything, yoga pants do. But here’s a sampling of what the science, much of it detailed in Broad’s book, says about yoga itself:
•It’s not a total fitness plan. Even vigorous forms don’t raise heart rates high enough, consistently enough to qualify as aerobic exercise on par with running, swimming or brisk walking. Yoga does help with flexibility and includes proven strength-building moves (yoga’s “plank” pose looks and works a lot like a push-up).
•It’s not a weight-loss plan. A typical session doesn’t burn a lot of calories, and it slows metabolism, which might even spur weight gain. But there’s a big caveat, Broad says: Yoga’s stess-reducing powers might reduce unhealthful eating.
•It may have heart health benefits. Most notably, it has been shown to reduce blood pressure.
•It has mental health benefits. One review of 80 studies found it equaled or surpassed other forms of exercise in reducing stress, anxiety and fatigue, lifting moods and improving sleep.
•It can ease some pains and inflict others. Broad tells gruesome stories of people crippled by yoga, including some who suffered strokes. But studies show yoga often soothes common aches — though one recent study on back pain showed that a specialized stretching class (which skipped the poses and breathing exercises unique to yoga) worked just as well.
Karen Sherman, a researcher from Group Health Research Institute in Seattle, led that study and says it remains possible that yoga has extra pain-calming powers. Sherman, who does yoga, also wonders “what would happen if we had depressed people with high blood pressure and lots of pain and they all did yoga. … Yoga might start to look better.”
The bottom line for Broad, 60, who also swims and lifts weights, is that he still practices yoga (but more carefully) and marvels at its potential.
He writes that yoga “can turn our bodies into customized pharmaceutical plants that churn out tailored hormones and nerve impulses that heal, cure, raise moods, lower cholesterol, induce sleep and do a million other things.”
Others who have looked at yoga research are not bowled over. Yoga is a glorified form of “light resistance training,” says Timothy Caulfield, a health law and policy professor at the University of Alberta in Canada, who has written his own book on diet, fitness and alternative medicine called The Cure for Everything: Untangling Twisted Messages About Health, Fitness and Happiness, to be published in the USA in April.
Like any form of exercise, yoga has benefits, he says. “But is there something special, unique or magical about it? No.”
For Neal Pollack, an Austin writer whose books include Stretch: The Unlikely Making of a Yoga Dude, “the real benefits of yoga are mental.” He says he has stopped using antidepressants and lost weight since starting yoga eight years ago: “It gives you an ability to slow down the pace of your life, calm your mind, and control your emotions. That’s got to be good for your health.”
He has been injured, he says, but “even after a bad yoga class, I feel better than when I went in.”
Kaitlin Quistgaard, editor of Yoga Journal, says that may be yoga’s greatest strength: “There’s this intangible benefit. It makes people feel good, so they keep coming back for more.”