Judith Leibowitz was 15 when she was stricken with polio. The disease ravaged the lower part of her body, and she spent the next six months in a hospital bed. "I didn't know the doctor had said I probably wouldn't walk again," she says. "If I had known that, I might have given up." Instead, the diminutive, dark-haired high school junior embarked on a program of physical therapy and, after six months, was able to get around on crutches and leg braces. But, she says, "because I have no normal muscles from the waist down, my body was quite distorted."

By the time Leibowitz returned to school, she was able to walk with a cane, but she had a very bad limp. She graduated from Brooklyn College in 1942 with a major in science and was working as a research chemist when a friend told her about the Alexander Technique, developed around the turn of the century by an Australian actor, Frederick Matthias Alexander. The gentle hands-on method of realigning the body and reeducating the musculature and the mind evolved from a nine-year period of Alexander's intensely studying his own movements to help cure a severe voice problem.

Skeptical at first ("It didn't jibe with my belief in 'the scientific method' "), Leibowitz began lessons anyway with Alma Frank in New York City. "She would say, 'Direct your neck to be free, let your head go forward and out into space,' and she'd simultaneously define what she meant with her hands," recalls Leibowitz. The final step was translating the release into movement, such as combing her hair, putting on her coat or, most important, walking. After a year of once-a-week sessions, Leibowitz took a month off from work to study every day. "By the end of that month I had lost most of my limp and body distortion," she says. "The change would have come eventually with weekly sessions, but more slowly. It was sort of miraculous."

Since then, Leibowitz, now in her 60s, has devoted most of her life to teaching the Alexander Technique to others. She studied with Alexander himself ("He wasn't a very good teacher, but he had fantastic hands") in the 1950s. In 1969, with four colleagues, she founded the American Center for the Alexander Technique, a licensed, nonprofit school on Manhattan's West Side. In 1968 Leibowitz was asked by John Houseman to introduce the method at the Theater Center of New York's Juilliard School—to help actors' movements onstage—where her students have included William Hurt, Kevin Kline and Patti LuPone.

Leibowitz is quick to point out that the Alexander Technique is not one of those tummy-tightening, get-thin-quick schemes, and at least 30 once-a-week sessions are needed to learn to use the Technique correctly. "People have to make a commitment to it," she says.

Why would they? According to Deborah Caplan, a co-founder of the American Center, "Just the stress of daily life can cause muscular-based problems from general fatigue to disabling back pain. The Technique provides a practical way of dealing with these conditions. It can be applied to activities like driving a car, working at a computer or bathing a baby. More and more physicians are referring back-pain patients to us."

The Technique involves no exercises, focusing instead on changing such everyday movements as walking, sitting, standing and the often harmful habits people have developed in accomplishing these movements.

It's not as easy as it sounds. The student's first job is to abandon old ways of moving and replace them by following verbal instructions from the teacher. During a typical session, Leibowitz teaches students how to rise from a sitting position: "Think of your head as a helium-filled balloon and your spine as the string attached to it. Helium is lighter than air, so the head is lifted and you take the spine with it." With that, the students rise to their feet in one fluid motion. As the movement is repeated, Leibowitz's hand, which is positioned at the base of a student's head, gently guides the motion.

Private lessons with Leibowitz, at the center or in her airy Manhattan apartment, cost $50 and last 30 minutes. "My students find their concentration is gone by then," she says. "It's very demanding to pay attention objectively to yourself."

But worthwhile. "I would come out of her class floating," recalls LuPone, a 1972 Juilliard grad. "Some of the Juilliard stuff we never used again, but not Judy's class."