The average age of the clients of the AgeWell Center is between 70 and 75. However, Holbrook encourages people to come in as early as 50 to begin minimizing the effects of age. The workouts help with balance and flexibility, as well as strength and cardiovascular conditioning. The drills are meant to help clients retain their mobility and abilities, even as time marches on.

Loss of muscle strength is one of the major reasons people end up in nursing homes, hospitals or with joint replacements.

"Our bodies are designed for physical activity," he said, "and you're never too old to get started."

He has one client who is 91, and many around Green's age.

Ric Collier began working with Holbrook to improve his ability to run distance races. Holbrook said age doesn't determine the workouts he plans for a client, but instead, he bases it on their needs and abilities. The AgeWell Center uses air-resistance machines, which are gentler on the joints, he said.

"I didn't want to injure myself," said the director of the Salt Lake Art Center. Then he began having ear pain and discovered a tumor growing in his left ear in March 2001. He knew he'd have to have surgery to remove the tumor, and was warned it could mean a loss of balance.

"I started reading Web pages, and I just got really depressed," he said. "I was so active, and some of these people took up to two years to recover."

So he talked with Holbrook, who had just the answer.

"We started working on a balance routine to help me recover quicker," Collier said. "Paul said you could literally train your muscles to compensate for the loss of the balance nerves in my ear."

He stood on one foot, caught a weighted ball and tried to balance his weight on what looked like a tiny wooden see-saw.

"It was like being an adult going to a kids park," he laughed. "Four or five weeks after my surgery, I went back to the gym. I could tell I didn't have the balance I did, but I came back stronger. . . . It was a remarkable adventure."

Many of those who work with the older population say their needs go largely ignored by traditional fitness clubs.

"That industry puts out a strong message and it's about vanity," said John Rudd, founder of Age Dynamics, which sets up wellness centers all over the country and offers support services as well as motivational material. "It's about looking good. . . . Those focused on the older population ask us to think about how we feel and how we function."