From a distance, they look like ordinary athletes. They run, swim, bowl and cycle.

But at closer range, they are anything but ordinary.

Spanning between 50 and more than 100 years old, the competitors are participating in the 2005 Senior Olympic Games, a national event that is held every two years and is being hosted this month in the Pittsburgh area.

How do the athletes stay fit enough to play as well as their grandchildren might? The question seems to plague spectators and scientists alike.

When asked how they maintain their stamina, many of the athletes shrug their shoulders - asserting no special measures to safeguard longevity. Some say they pay moderately close attention to diet, but none claim to be restrictive.

Most, however, have maintained some level of physical activity through all phases of their lives."I just take a vitamin, and that's it," said Marylee Medve, 69, of Slippery Rock, who is competing in the swimming events. "I have five children and a husband. I've tried to be as active as I could. I was active with the kids - running around with them."I would take them to Lake Arthur. Parents usually say, 'come on kids, let's go home.' But they would be telling me it's time to go home. I've always loved to swim."Connie Haswell, 65, of Connoquenessing Township, has also tried to remain on the go."I've always been an active person and I've always been athletic," said Haswell, who is competing in the basketball events."I've been a homemaker most of my life. I've raised children and been a homemaker, so I think that kind of keeps you active. You never retire. You go from one thing to another.Although Medve and Haswell compete successfully now, neither said they spent their entire adult lives training. Like many now taking part in the Senior Olympics, their role in sports was displaced for long periods by the responsibilities of careers and parenting.Although she played basketball in high school, Haswell said she's only been playing in the Butler Cubs league for four years.Medve said she didn't begin swimming regularly until after the age of 50. Now 69, she swims 2,000 to 2,500 yards three or four times a week.Tom Murray of Zelienople began running in his early 40s. Now 63, he is competing in cycling races and the triathlon.The triathlon includes a 400-meter swim, a 12-mile bicycle ride and a three-mile trail run.In addition to entering his fourth round of the national senior games, Murray competes in the World Iron Man championships in Hawaii. The Iron Man consists of a 2.4-mile swim in the ocean followed by a 112-mile cycling link and a 26-mile marathon."I never thought I would be doing anything like that," he said, "but it's surprising what you can do if you're willing to do the training and have the discipline and the determination to do it."You have to build up to it. I started out just running a mile or two, then built up to do local 10Ks. Then I had a desire to see if I could compete in a marathon. I was able to do a few of those, so then I developed an interest in the triathlon."

Murray said he now does around 15 races a year."Looking back, at age 30, I would (have been) happy just to live this long," he said. "I wasn't very athletic."Although the athletes project an image of vitality, many are quick to point out they aren't immune to the hazards of aging.Joy Brewer of Zelienople, who is competing in volleyball and basketball, was undergoing chemotherapy for breast cancer last year while competing at the state level."They're saying if you walk three to five miles per week after breast cancer, chances of recurrence are greatly diminished," the 57-year-old Brewer said."I was walking 10 miles a week prior to cancer - and I still got it. It was a shock, because I felt very healthy. I was doing the same things that I'm doing now."Even so, Brewer said she suspects her fitness level helped provide her the strength to undergo treatment."Because I exercise, I have lots of stamina," she said. "I don't have to take naps during the day. I don't get tired out as my day goes on."I'm no less active now than I was before the cancer. I was a three-sport athlete before I had the cancer."Many of the senior athletes say their biggest fears center on injury. Like Brewer, many say they "play through the pain" when illness and injury occur.

Dr. Vonda Wright is a research coordinator at the senior games and a clinical instructor in the University of Pittsburgh School of Medicine's department of orthopedic surgery. She said while no studies show that playing sports fends off the ailments related to aging, it seems senior athletes aren't deterred by maladies.As an orthopedist, Wright sometimes recognizes signs of arthritis and other age-related ailments by the way athletes are walking and by the shape of their legs. In these cases, Wright said she is not surprised the athletes say they continue playing despite some discomfort.Wright said even though the athletes' rate of age-related ailments hasn't been studied, University of Pittsburgh researchers did advance their knowledge of senior athletes after beginning a health survey during the 2001 games.The study shows more than half of the female competitors have normal bone density, which contradicts data on the general population.The athletes also reflect higher mental and physical health summary scores as compared to averages for their age groups.A significant finding, however, is that 75 seems to be a critical age for physical decline."We get moderately slower between 50 and 75, but our performance changes dramatically between 75 and 85," Wright said.At the University of Pittsburgh's Center for Healthy Aging, director Connie Bayles is working with prevention in mind. After a 3½-year study of 550 people in Allegheny County, the center has come up with 10 keys to healthy aging"I think your genes play a very big role in your health, definitely," Bayles said. "but prevention should be at the forefront of any health plan."Bayles said that plan should include preventing bone loss and muscle weakness, controlling blood pressure, regulating blood glucose, not smoking, maintaining social contact, participating in cancer screening, getting regular immunizations, lowering cholesterol and combating depression.But exercise, of course, is also important, said Bayles. The athletes at the senior games offer a fine example."I think people will be very surprised when they see some of the (Senior Olympics) coverage on TV," Bayles said. "These people are in really good shape.People who exercise are usually happy."Haswell agrees. That's why she's taking the opportunity to compete in this year's games.I think it's important to continue to stay active," she said, "and to find things to do that you enjoy doing."--------On the Net:The 2005 Summer National Senior Games - The Senior Olympics, www.2005SeniorGames.org