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The Science of Yoga destroys the activity's top myths

The Science of Yoga
William J. Broad
Simon & Schuster

Ever wonder if that headstand you're doing is good for you? Or if your Ashtanga practice is really giving you an aerobic workout? Or if your yoga teacher is truly qualified to be teaching?

Enter William J. Broad. He has wondered, big-time. A long-time yoga practitioner, Broad is co-author of the formidable Germs: Biological Weapons and America's Secret War and a senior writer at The New York Times. He may now be the Shiva (destroyer or transformer) of yoga as we know it.

In The Science of Yoga, a landmark exposé, he is the destroyer of the top myths rampant in yoga, a destroyer of some of the master gurus' teachings and, perhaps, may soon be a destroyer of the unregulated system of teaching yoga and of yoga therapy.

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Broad is mad as hell and, luckily for us, he's not going to take it any more. He knows (as a yogi for about 20 years) that yoga has a great capacity to heal body and soul, but he believes that the cobwebs of myth need to be cleared before all soul is lost.

"Yoga had gone from an ancient obsession with transcendence of the body to a modern crusade for a new kind of physicality," Broad says, proceeding to lay bare some of the more cringeworthy myths, "miracles" and risks of yoga in his brilliantly researched work.

He forewarns us that he's going to focus "relentlessly" on what science tells us about postural (hatha) yoga via interviews with scientists and physicians, and with selections from the almost 1,000 yogic studies on PubMed. And he does so by creating a story that uses historical and social context.

He starts by zeroing in on the myths begun a century ago by overzealous and scientifically naive yogis – that yogis are able to bury hemselves for 40 days and emerge alive, yogis can stop their hearts at will (as Yogananda claimed they could), and that deep pranayamic breathing floods the body with oxygen.

Studies find holes in all those claims. Master yogis had to emerge from their coffins breathlessly after just l8 hours; heartbeats don't cease – electrodes captured their faint blips (as with the renowned T. Krishnamacharya when he agreed to be tested); increases in oxygenation have nothing to do with the lungs (nor, apparently, fast pranayamic breathing or hanging upside-down), but rather with the heart (as discovered by the 1922 Nobel Prize-winning physiologist Archibald Hill).

Broad then addresses the top yogic myth of today – that yoga is a great aerobic fitness workout, a myth perpetuated by Bikram Chouldhury and leading yoga magazines. "My classes are so hard," Choudhury boasts, "you use your heart more than if you run a marathon."

Well, apparently not even a half-hour of sun salutations or a full Power, Ashtanga or Bikram class will significantly boost the VO2 max, or maximum oxygen intake in scientific terms. With the rising popularity of yoga in the 1970s and 1980s, Broad says, scientists couldn't resist testing the various aerobic claims.

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Yoga magazines grabbed any crumbs they could from the resulting research , claimed victory, boasted aerobic prowess, and the truth "rapidly sank into the void of cultural forgetfulness," Broad says. For example, yoga was heralded for boosting VO2 by seven per cent, but that hardly compares with 50-per-cent gain athletes get from endurance training.

Some myths can lead to taking serious risks, Broad shows, such as the ones that claim headstands or Wheels or bending one's head far back in Cobra are good for you, when instead they can sometimes cause strokes, nerve damage, paralysis and even death.

The head should arch "as far back as possible," suggests B.K.S. Iyengar, a guru to millions, in his bestseller Light on Yoga.

The number of people injured annually would look like a minor percentage of the population if it weren't for Broad extrapolating the worldwide number and the U.S. Consumer Product Safety Commission reporting that yoga injuries have soared since 2000. One survey showed that most yogis felt incompetent teachers were the cause.

For every cloud, however, there is a silver lining, Broad says, and in his chapters on mood, healing and divine sex, the lining really shines . Impotent? Yoga is probably better than Viagra, increasing testosterone levels by up to 33 per cent in males. Yoga is shown to help ward off major depression (with levels of the GABA neurotransmitter increasing by up to 80 per cent), reduce hypertension, reduce vertebral disc degeneration, boost immunity and increase longevity (with levels of telomerase – an enzyme that maintains DNA in chromosomes – increasing by as much as 30 per cent).

And this is just a sampling of what Broad exposes to the light. He ends by admitting that advanced yogis "may frolic in fields of consciousness and spirituality of which science knows nothing." But why not use science to understand this ancient, mysterious practice as much as we can?

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