The Science of Yoga

tough and prickly. He would tease Fishman, saying the eager student had deluded himself into thinking he understood the Iyengar system.
    Finally, after a year of instruction, Iyengar ordered Fishman to go home and start teaching. Fishman did so. But he also decided to get as serious as he could about healing and went off to medical school—Rush Presbyterian St. Luke’s in Chicago, one of the oldest and most respected medical schools in America. It was founded in 1837, two years after the inauguration of the Bengal Medical College, a half a world away.
    Today a growing number of physicians study yoga after medical school. Fishman was one of the first to do so beforehand. His medical immersion when he was already an advanced student of the discipline let him see yoga through a Western lens, understanding its routines in terms of the fine distinctions of anatomy and physiology, chemistry and physics. In some respects, he was able to fuse the West’s storehouse of scientific knowledge with the inspiration of Iyengar’s visceral creativity. It was a fresh approach that bristled with possibility and seemed to offer a new way to minister to the world.
    Fishman graduated in 1979 and did a psychiatric internship at the Tufts Harvard Medical Center in Boston, eager to help troubled minds. But he found it unsatisfying and instead threw himself into rehabilitative medicine.
    The field seeks to help individuals with broken bones, torn muscles, dead nerves, injured tissues, and other physical disabilities. Its rehabilitations draw on a wide variety of tools and treatments. Standard ones include slings, braces, crutches, drugs, prostheses, walkers, physical training, therapeutic exercise, and many adjustments to the lives of patients.
    In Fishman’s case, the options include yoga.
    Few locations in the world of medical real estate are classier than 1009 Park Avenue in New York City, between Eighty-Fourth and Eighty-Fifth. It has a large but discreet awning and the usual glint of polished brass. The old building is as elegant as any on the Upper East Side. The 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