FREMONT - Grabbing her walker, Sister Magdalene Robles stood up and pointed straight ahead to the exercise room at On Lok SeniorHealth's center.

"There's exercise," she said, and set out in her black veil, white smock and stockings, slowly but deliberately lifting one foot forward, then the other.

Moments before, an electric wheelchair had pulled up beside her. "She's made a lot of progress," said the passenger, referring to a stroke that Sister Magdalene, 83, had a few years ago. "She was in a wheelchair and she used to cheat when she walked, holding onto the wall. But look at her. She's walking."

"What about you?" asked the visitor to whom Sister Magdalene's friend spoke.

"Oh, I do fine," she said, and whizzed away.

Arriving at her destination, Sister Magdalene joined a circle of sisters in their 70s, 80s and 90s. All had their eyes trained on Laurie Turnage, the center's recreation therapist.

"Cross, cross, cross," shouted Turnage, as the women in their habits sat in chairs, held their arms straight and crossed one over the other. "Circle your thumb ... your index finger ... your middle finger ... your ring finger ... your baby finger," Turnage said, and they dutifully obeyed. "Circle your wrists, around and around."

The container for the exercise class was a health center, built three years ago on the north side of the Sisters of the Holy Family's main house. The Fremont facility is one of six Bay Area centers run by On Lok HealthServices, an HMO that takes an alternative approach to elder care.

Chair aerobics won't be found at most convents, but it is a regular activity at the Sisters of the Holy Family in Fremont. Many of the women (who are known as sisters, because they are not cloistered like nuns) still have sharp minds, and the center helps them stay mentally and physically healthy. On Monday through Friday, sisters from the convent and the Dominican Sisters of San Jose -- its neighbors from across the street -- can be found doing aerobics, doing physical therapy or talking about current events.

On Lok focuses exclusively on frail seniors; its mission is to help them remain at home and out of nursing care. So, unlike traditional HMOs, which pay for services and leave most care decisions to doctors and patients, On Lok plays a more active role, of which the centers play a central part.

To enroll in On Lok, a member must live close to a center and visit at least once per week for meals, exercise or other activities. The HMO also aids members who need help at home; at the two convents, it provides 24-hour care for sisters who need it.

To keep members as healthy as possible, the HMO aims to catch problems early. It enlists everyone who has contact with participants -- from the drivers who bring them to and from the centers to the social workers who monitor their lives at home -- to watch for changes.

At an early morning meeting, a team of On Lok caregivers -- including an occupational therapist, physical therapist, social worker, recreational therapist and doctor -- gather at the Fremont center, one of four meetings held per week to discuss patients' latest developments.

At the top of the agenda is a sister who has fallen twice in the past 24 hours. Her ankle is fractured and still she keeps climbing out of bed. The discussion circles around whether to place a special bed in her room to stop her from getting up.

"She's going to fight it," says Anne Cockle, the occupational therapist. "She'll figure out how to operate it."

"Can the family call and talk to her?" asks another team member.

By family, she doesn't mean the sister's blood relatives. Rather, she means church superiors, to whom the sisters have taken vows of obedience. This is the team's trump card. When instructions are ignored, they often ask the "family" for help.

Lucienne White, the registered nurse, reports that another sister's "family" wants her eating in the dining room instead of in her room, as she has lately.

A few team members are concerned because she is more nervous than she used to be. "I don't know that it's the best thing for her," said Caroline Shobert, the social worker. "It's a big dining room. It might just tip the scales for her. ... . A person like that just wants to pull the blankets over her head."

"Maybe the family needs to take her to the dining room and see what she does," said Cockle.

They decide to test the dining room for a few days and then re-evaluate.

The issues raised by the team might seem trivial because, in many cases, they only peripherally deal with actual medical care. But the attention to detail is important for On Lok's holistic model of care. Care plans include medications and physical therapy regimens but also more mundane particulars of life. For example, if a member needs an air conditioner, the HMO will pay for it. Or, if members need help with housework or cooking, that also will be provided.

Amazingly enough, the approach saves money because its members stay healthier, said Robert Edmondson, On Lok's director. On Lok receives less money than nursing homes from Medi-Cal, but it still can provide more services, he said.

"The beauty is," he said, "we feel like the quality of life is better."

On average, participants of On Lok and its national counterpart called PACE also spend fewer days at the hospital than Medicare patients, said Cathy Eng, a staff physician at On Lok and clinical professor of geriatrics at UC San Francisco.

So far, On Lok has six San Francisco centers, plus the one in Fremont, plus two San Francisco centers that contract with On Lok -- with 960 members.

There's an obvious need elsewhere in Northern California, Edmondson said. But the HMO is cautious about growth; it doesn't want to expand at the expense of quality, he said.

For the Sisters of the Holy Family and Dominican Sisters of San Jose, On Lok has filled a big hole.

Traditionally, convents have relied on younger sisters to care for the older ones. However, as is the trend across the country, few younger women are taking vows at the Fremont convents. The median age of the Sisters of the Holy Family is 72. The average age of those enrolled in the Fremont On Lok center is 85 (one sister is 103).

Most sisters qualify for Medi-Cal, the state's insurance for low-income families, seniors and the disabled, but that doesn't include home care. Under Medi-Cal, the sisters would have had to move to nursing homes to get the attention they needed, a step the convents didn't want to take.

Accordingly, before they found On Lok, the two Fremont convents had little choice but to pay for skilled nursing home care. But the high costs vexed the convents. It diverted money from their mission to serve the needy and the poor.

In 1997, the treasurer of the Sisters of the Holy Family returned from a conference excited about a program called PACE, which stands for Program for All Inclusive Care for the Elderly.

"This might just be the thing we're looking for," she told Sister Sharon Flannigan, the convent's congregational president.

Sister Sharon called the Milwaukee convent that had tried PACE, only to discover that the program had originated at On Lok, in San Francisco's Chinese community.

Concerned about its aging seniors, leaders of the Chinese community had hired a consultant in the 1970s. The consultant, named Marie-Louise Ansak, came up with a plan to build adult day centers where seniors could receive care, but still live at home.

Several years later, On Lok added home care. Eventually, the program also included full medical insurance.

In the early 1990s, the program was replicated at eight sites across the country under the PACE moniker. In 1997, the federal government recognized PACE as a permanent benefit under Medicare and an option for all states. On Lok receives government funding from Medicare, and also Medi-Cal. Members who do not qualify for Medi-Cal pay a monthly premium of about $3,000.

It took five years of navigating bureaucracy and about $2 million to build the On Lok Fremont center, but it was well worth it, Sister Sharon said.

The program saves the Sisters of the Holy Family more than $500,000 a year. And the sisters love it -- at the center, they can exercise, socialize, keep their minds ticking and even make new friends.

That the On Lok program is mostly supported by the government doesn't bother Sister Sharon.

"We need to be mindful of our elders," she said. "It is the responsibility of our country to pay attention. ... I think we are judged by how we take care of the poor, the children and the elderly."

The Fremont center includes two pristine, somewhat small, white-walled rooms: one for physical therapy, the other for recreation. There's also a medical clinic, staffed full time by a licensed vocational nurse and a registered nurse, as well as a doctor who visits three times per week.

From 8 a.m. to 4:30 p.m., the sisters fill the center. In the physical therapy room, they rotate among simple pieces of equipment. There are parallel bars where they can practice walking or do toe-rises to strengthen calves; a rope pulley for the arms; and Nustep for the legs, the most popular machine among the sisters.

In the recreation room, the voice of Turnage, the recreation director, rings out throughout the day. On a Tuesday morning, she moves onto current events after leading stretching exercises. Sitting with her legs crossed and the newspaper opened wide in front of her, she relays a synopsis of selected stories. The sisters are alert and pay close attention, their eyes fixed steadily on Turnage.

"There was a Greyhound bus crash Saturday morning," Turnage says. "Two people died. It says that there wasn't a mechanical problem, that it was driver fatigue."

"Isn't that terrible," comments one sister.

"There was a woman who was seven months pregnant," says another.

Turnage moves onto sports, a favorite among the sisters. "Sister Eunice, are you following the A's?" Turnage asks. "They're trading people."

Later, Turnage turns to a new game, called "Things that Used to Be," where she names objects, people or events from the past. "Do you remember hat pins?"

"Oh yes," replies one sister. "Veil pins," and reaches up to touch her hair.

"In those days, we had more hair than we have now," says another.

"Some women used hair pins as a weapon," pipes in someone else. "Some guy got fresh and they took a hat pin at him."