ALBANY – Bonita Claytor was pushing a cart bearing a 500-pound liquid nitrogen cylinder when the small steel wheels got caught on the leading edge of a carpet. She tried to tilt the cart and landed in the hospital.

“I lost the feeling in my foot and my leg,” said Claytor, 42, a lab technician at Chevron Research Co. in Richmond. “I didn’t know that 1 had hurt my back.”

The jelly-like substance in the disk between Clayton’s lumbar vertebra and sacrum had herniated, or squirted out, and was pushing on her spinal nerves, causing muscle weakness. and severe lower back pain.

Now Claytor, 42, of East Richmond Heights feels pretty good.

She credits a month of twice-weekly exercise sessions in the Albany Pool with allowing her to get off pain medication and ease back into her normal routine.

She was at the pool Thursday doing jumping jacks and bicycle-pedaling.

“While you’re in the water, you don’t feel the pain,” she .said. “I can. walk a lot better now; I’m not limping as much. My stamina is better.”

Aquatic therapy, also known as hydrotherapy or water therapy, is fast gaining acceptance as the exercise of choice for people recovering from a variety of ailments.

And since it is less costly than physical therapy, more and more insurance companies are paying for it.

“The industry just exploded in ’94,” said physical therapist Alan Ling, a former employee of Brookside Hospital in San Pablo who now runs his own clinic, Physical Therapy Innovations of EI Cerrito.

The body’s natural buoyancy in water counteracts the stress of the body’s weight on the spine on land, allowing certain muscles to relax in a way they can’t outside the water.

“In warm water, people don’t tense up,” said Mary Essert, Ling’s business partner and a part-time employee of the Albany Unified School District, which owns the pool.

“On land, you’re always fighting gravity,” Ling said while massaging Barbara Chill during Thursday’s. exercise session.

Chill, 55, a warehouse worker at Costco in Richmond has had lower back pain since a wooden table fell off a cart onto her ankle at work. The pain sometimes extends down to her leg, she said.

The massage stimulates the blood supply to the injured areas, Ling said.

The principles behind water therapy are not new.

“Hydrotherapy has been around since the Romans in the fourth century (A.D.),” said Essert, an EI Cerrito resident who has published articles and has lectured nationwide -on fitness, especially in older people.

Most water therapy patients are aging baby boomers, many of whom injured their joints running, and older people, Essert said.

But pregnant women, people recovering from strokes and those with . various degrees of paralysis also benefit from the treatment.

The group at pool Thursday consisted largely of people with back ailments like Clayton and Chill, but a few people were being treated for arthritis or newly healed fractured limbs and joints.

Some did jumping jacks and cross-country skiing motions, while others walked or ran forward, backward or sideways, using their (arms and legs for locomotion, controlling the intensity of the exercise by varying the leverage and range of motion of their limbs, as Essert said.

Others wore flotation belts of varying degrees of buoyancy, which encourages them to flex at the waist, to protect the lower back. This strengthens the abdominal and back musculature, Essert said.

Reprinted from Sept. 3, 1995