The Science of Yoga

office sits amid a constellation of physician specialists up and down the wide boulevard and across the street from the tall spire and Tiffany glass of the Park Avenue Christian Church, a neighborhood icon. The Plaza Athénée lies twenty blocks south.
    Inside, nothing suggests the office is special. It has the usual art and magazines. The main hint of individuality lies behind the receptionist—a large shelf of Fishman’s books on yoga therapy. They discuss how to treat everything from multiple sclerosis to sciatica, the condition in which irritation of the sciatic nerve causes pain to radiate through the buttocks and down the leg.
    I learned of Fishmanwhile looking for ways to strengthen my back. His book Relief Is in the Stretch: End Back Pain Through Yoga prescribed what seemed to be a sensible regime of postures. I especially liked his explanation for what stretching did. He told of a hidden interplay between two kinds of sense organs woven into the body’s tendons and muscles. As a muscle stretched, he wrote, the two systems sent conflicting signals. Contraction was stronger than relaxation, so the muscle stayed tense. If the stretch continued, however, that signal began to diminish of its own accord and the relaxation impulse started to dominate. The transition took time, Fishman wrote. It started as the stretch continued from fifteen to thirty seconds, and the relaxation signal grew to dominate in less than two minutes.
    That mechanism, Fishman wrote, is why students of yoga should hold poses patiently—at a minimum, fifteen seconds to two minutes. Only then can the muscle relax enough to stretch farther. He said the lengthening can dramatically help victims of back pain. It can increase the range of normal motion, relaxing the spinal regions and leaving them more supple, flexible, and resilient. And that in turn can help avoid conditions that lead to muscle spasm—the sudden, involuntary contraction of muscles, sometimes accompanied by great pain.
    I enjoyed not only Fishman’s clear writing but also his earthiness. Many yoga books use fashion models to illustrate the poses. Fishman, lithe and limber, often modeled them himself.
    He appeared in the reception area, saw a patient, and gave her a hug and a few encouraging words. He was short and wiry, a bundle of energy, his smile quick. He wore a pale-blue shirt in a checkered pattern and a discretely colorful bow tie.
    We went into his office and he spread out trays of carryout sushi. The wall behind his desk was cluttered with the usual diplomas as well as a large photograph of Iyengar. The famous yogi sat in a Full Lotus, his head high and eyes open, a picture of pride and vitality. Nearby photos also showed two grown children in graduation caps and gowns. From my research, I knew Fishman had achieved quite a bit in his career. In addition to treating patients, he held a clinical professorship at the Columbia College of Physicians and Surgeons, the medical arm of Columbia University. He had published more than a hundred papers and articles. At one point, Fishman led the New York Society of Physical Medicine and Rehabilitation, serving as itspresident. His thriving practice, Manhattan Physical Medicine and Rehabilitation, employed physicians at four offices around the city—on Park Avenue, on the Upper West Side, in Queens, and on City Island. He also served as treasurer of the Manhattan Institute for Cancer Research, a charity.
    While eating, Fishman told of his therapeutic work. Often, he would jump up from his desk to show what he meant, either doing a pose or demonstrating his point on a human skeleton hanging nearby. He said he was sixty-six but looked to be in his fifties.
    Yes, he said, he learned much from Iyengar. But as Fishman spoke, it became clear that his guru was no guru in the sense of being a role model he followed slavishly. Instead, Fishman honored his mentor by exhibiting the same kind of pigheaded independence that Iyengar did, trying things on his own, experimenting on himself and his patients, arriving at cures and treatments in a roundabout way. It seemed that Iyengar provided the context, not the content. Fishman seemed to be a modern thinker who liked to tinker, a kind of Thomas Edison of yoga therapy.
    He told of his own painful experience with torn rotator cuffs, and how that led to what he called a miracle cure. He used the phrase with a wry smile.
    The shoulder is the most flexible joint of the hundred and fifty in the