The Science of Yoga

deserves your attention and—perhaps most important—your money. Remarkably, he even rejects all other styles of yoga. A standard estimate for the number of people in the United States who do yoga is twenty million, and Choudhury happily cites that number as representing a world of misguided souls.
    “Bogus yoga” is what he calls their practice. He ridicules other approaches as watered down to accommodate American weakness and inflexibility. Among the competition, he scoffs at Kundalini, Ashtanga, and Vinyasa (“which never existed in India”), as well as Iyengar (“he uses so many props in his method that he’s called ‘The Furniture Yogi’ in India”). The newer yoga brands, he added, are even more ridiculous. “You’ve got Easy Yoga, Sit-at-Your-Desk Yoga, Yoga for Beginners, Yoga for Dummies, Yoga for Pets, and Babaar [ sic ] Yoga. It’s all Mickey Mouse Yoga to me.”
    The false prophets, he charges, shirk their responsibilities to ancient tradition and cheat students out of “the perfect life,” keeping them from the rewards of “optimum health and maximum function.” In contrast, he portrays his own style in cartoonish superlatives: “You’ll become a superman or a superwoman!”
    Is he right? Is there more substance to hot yoga than Bikram’s boastfulness would imply? And what of the other styles? Are there objective measures that can establish the benefits and compare them to regular exercise and sports? In short, is it possible to find out what is real and what is not?
    While the scientific investigations of yoga over the decades have tended to be sketchy and idiosyncratic, the subject of physical fitness is one area that has received a fair amount of scrutiny. The reason has to do with the prickly nature of intellectual turf.
    The academic world has a number of research fields that lavish attention on questions of fitness. The disciplines include biomechanics, kinesiology, exercise physiology, nutrition, physical therapy, and sports medicine, among others. Today, sports scientists draw on a wealth of instrumentation and software to conduct careful studies of exercise and athletics. Whole businesses do nothing but sell the equipment. Major universities have whole departmentsthat do nothing but conduct fitness studies and publish the results in dozens of specialty journals, including the Journal of Exercise Physiology and The American Journal of Sports Medicine. The field’s textbooks tend to be gargantuan in size and extraordinarily detailed in content. The professional societies of the field include the American College of Sports Medicine—the world’s largest organization of scientists devoted to the study of athletics. Its standing is such that governments around the globe routinely adopt its guidelines for physical activity in campaigns meant to promote public health.
    Yoga’s fitness claims fall squarely into this whirl. A philosopher would say they fall within an existing paradigm. The situation is very different from the case with yogic declarations about, say, body currents and spiritual renewal.
    As a result, a relatively large number of scientists (a growing number of them yogis) have applied the instruments and the techniques of the academic sports establishment to the study of yoga’s fitness claims. The results, as we shall see, raise significant doubts about some of modern yoga’s most prominent declarations.
    A complicating factor is that yoga, taken as a singular activity, represents an oversimplification rooted in the discipline’s timeless image. A better word would be “yogas,” denoting the evolution of many styles over the centuries—with new ones appearing all the time. Three phases stand out. First was the original Hatha, which debuted as a forceful branch of Tantra. Then, as we saw in the previous chapter, the yoga innovators of the early twentieth century produced a sanitized Hatha. Today, the newest styles represent another step in yoga’s development, their moves more vigorous than the old. It turns out that modern yoga, by accident or design, has lost much of its contemplative nature and adopted some of the sweatiness of contemporary exercise.
    Gune taught a style of yoga that epitomized the slow, tranquil approach. His emphasis was on holding poses for long periods of time and learning how to relax even amid extreme states of bending, flexing, and upending. It was a point he drove home with his measurements of how challenging inversions were