This Magnum Photos gallery will make you feel like stretching.
Some things feel better than they look. One day, in the Indian Himalayas, I came across a sign that read "Himalayan Iyengar Yoga Institute" and indicated a rocky path. About half a mile down the path was an empty courtyard framed with flowers, along with a bulletin board with photos tacked to it. Curious, I examined the photos, which showed what looked like normal men and women tied up with ropes, hanging upside down, supported by slings. Knowing nothing else, I might have taken it for an exhibition of torture or Japanese rope bondage. But here was the strangest part of all: Each person wore a beatific smile not unlike that of a teenager in love.
Intrigued, I enrolled in the weeklong introductory course. The instructor, Sharat Arora, a disciple of B.K.S. Iyengar himself, welcomed us to class by silently staring at each student for an extended period. During instruction, he vacillated between cruelty and kindness with memorable abruptness. But what I remember best is the day he tied us into a position called "supported plow." The procedure demanded ropes, blankets, and stools. It fell short of elegant. Yet so perfect was the stretch that it led me to what can only be described as a kind of semiconscious trance. Afterward, the world seemed nicer, softer, and more colorful. It seemed that my blood had turned to wine. Nothing has been quite the same since.
That Iyengar experience left me wondering: How, exactly, can simply bending your body have such a transformative effect on the mind? What, exactly, does stretching do to your brain?
That's a question that the physical side of Indian yoga was developed over centuries to try to understand. Here in the West, meanwhile, the question was of considerable interest to psychologists and others in the early 20th century. Carl Jung, the Swiss founder of analytical psychology, saw in yoga's stretches a potential replacement for some of the Catholic ritual that Protestants had relinquished and an unrivaled means of uniting body and spirit. As he wrote in 1936, "When [in yoga] the doing of the individual is at the same time a cosmic happening, the elation of the body (innervation) becomes one with the elation of the spirit (the universal idea), and from this, there arises a living whole which no technique, however scientific, can hope to produce." Despite his enthusiasm, Jung nonetheless warned that yoga practice was probably unsuited to the "divided" Western mind.
Another early follower of Freud's, Wilhelm Reich, had the same intuition that the yogis did, believing that the point of the psychological method was the physical release of trapped energies. Hence, as professor Paul Johnson of Stanford University describes it, Reichian psychoanalysis in the 1930s resembled Thai massage. "Successful psychotherapy involved relaxing taut muscular structures, beginning with the forehead and moving downward toward the pelvis. With the elimination of the final muscular blocks, the patient would break down in involuntary convulsions, which Reich termed the 'orgasm reflex.' " As this suggests, although today we might blame a lousy office chair for back pain, Reich believed that all deep muscular tension ultimately came from sexual frustration. Consequently, the whole point of therapy, in Reich's words, was the "complete discharge of all dammed-up sexual excitement through involuntary pleasurable contractions of the body." It may be sentiments like this that contribute to the impression, particularly among the repressed, that there is something unseemly about yoga practice.
If that sounds a little extreme, in 1910 a man named D.D. Palmer theorized that not just mental illness but all diseases were caused by misalignments of the spine, the classic location of inaccessible muscle tension. He called these misalignments the problems of "vertebral subluxation." "I firmly believe," Palmer wrote in 1910, "that there is no diseased condition of the body that is not directly caused by a sub-luxated bone which interferes with the nervous system in some way." Palmer went on to found what he called "the chiropractic" (which spawned chiropractors). Like yoga, the chiropractic appeals to that instinctive sense that your problems might disappear if only you could get your alignment just right.
In 2010, it is rare for medical doctors or psychologists to rely on stretch to treat mental or physical ailments. Consequently, as my Iyengar experience suggests, yoga has taken over as the high church, fulfilling, to some degree, Jung's prediction. While people begin yoga for all kinds of reasons—exercise, stress reduction, or acquiring "yoga butt"—I suspect that just one thing keeps them coming back. It is that supreme moment of satisfaction achieved in the perfect stretch. Lauren Magarelli, a yoga teacher at New York's Laughing Lotus studios described the sensation memorably: "You feel a shift. It's like being subtly intoxicated. It's bhavy."
The perfect stretch can happen in many of the important yoga poses (potentially, I suppose, in any). You may find it in pigeon pose, a hip stretch that, at times, can release a comfort and joy that reminds you of Christmas morning. The sensation is found in the many moves that twist the spine, where the sensation is akin to wringing your body like a wet towel. Or in the so-called "heart-openers," like the scorpion pose, that suddenly and genuinely make you want to be kinder to strangers.
In short, it feels good, so good that a college friend once told me that she had quit yoga because she had become too addicted. Indeed, yoga addiction is not uncommon, even though the poses are meant to be a release from desire, not the object of it. As Cyndi Lee, the founder of New York's OM Yoga pointed out to me, yoga addiction is just a different version of "goal-oriented yoga." When you see the look on the faces of people rushing to make class, you can sometimes tell that the obsession has taken hold. It can be hard to avoid wanting that feeling of not wanting anything.
If there's an intuitive link between stretching and the mind, what is the science behind it? I asked a friend who was once a neuroscientist (the monkey and kitten experiments got under his skin), and he explained that understanding "brain-body feedback loops" is critical to understanding the emotional effects of stretch. Consider that if a patient is given drugs—beta-blockers to slow the heart, for example—he'll begin to feel relaxed, because the brain interprets the slow-beating heart as a signal that it should relax. Similarly, the very act of smiling has been shown to make people happy. If you induce a rapid heartbeat, the patient begins to feel nervous and anxious. All these are feedback systems: The mouth and the heart are telling the brain how it is supposed feel.