Swimmer Leianne Crittenden recently has racked up a national championship, a world championship and a world record, but she's not some promising college athlete.

Swimmer Leianne Crittenden recently has racked up a national championship, a world championship and a world record, but she's not some promising college athlete.

"For an old lady I do OK," the 51-year-old attorney and masters swimmer says with a laugh. "When I go against 20-year-olds, sometimes I beat them. I think they're sort of surprised — they say, 'Who is that woman with the wrinkles?' "

Crittenden isn't an anomaly. The notion that age offers only diminishing returns when it comes to fitness is being blown to bits — particularly in endurance sports. Events that require pacing, strategy and mental fortitude are where many older athletes, especially women, excel.

Suzanna Bon, 43, was the top female finisher at this year's Angeles Crest 100 Mile Endurance Run in the Los Angeles area, also setting a course record. Forty-year-old swimmer Dara Torres might make history in the 2008 Olympics as the first swimmer older than 40 to compete in the Games. And Valmir Nunes, 43, won the Kiehl's Badwater Ultramarathon this year, a grueling 135-mile run from Death Valley to Mount Whitney in California.

Exercise and sports-psychology experts think there could be more to this success than physiology and good genes.

"I think there are a number of things that people do better as they get older," says Miriam Nelson, director of the John Hancock Center for Physical Activity and Nutrition at Tufts University in Medford, Mass. "They're more disciplined, they train smarter, they're consistent with their training. Whatever sport you're in, you can be smarter from a competitive edge in terms of knowing yourself, how to pace yourself."

In marathons, for example, runners in their 20s often sprint out of the starting line, whereas older runners stick to a more prudent strategy that doesn't burn them out before the finish line.

"Take a 30-year-old athlete who's vigorously active, at the top of their career," Nelson says. "If they continue what they're doing, they'll be able to hold onto that for some time." That also holds true for those who stay on a steady routine of moderate to vigorous exercise.

"A 75-year-old," Nelson says, "will be more like a sedentary 35-year-old if they're fit."

That's not to say biology doesn't play a role. Younger people generally have better coordination and balance, which allows them to do better than older people in sports such as gymnastics. As people age, reflexes slow, and proprioception skills — sensing where one's body is — diminish.

But life experience shouldn't be underestimated.

Older athletes "know how to use what they have," says sport psychologist Ralph Vernacchia , director of the Center for Performance at Western Washington University in Bellingham and a professor in the physical education, health and recreation department. "If they only have 60 percent of the functional capacity and aerobic power they had when they were much younger, they can learn to get 100 percent out of that 60 percent. They're better at strategizing. As we age, we recognize that we're not going to waste the time we have. ... Having that mental resilience and attitude is so important."

Many also learn how to train smarter.

Masters swim coach Kerry O'Brien tries to make the most of his swimmers' hour to train. Between jobs, family and other obligations, his team can't spend endless time in the pool like some of their younger counterparts.

Instead, they hit high-intensity levels during freestyle swims first. "We try to tax the body, get it tired, then do pace work for specialty strokes," he says. Swimmers get the workouts they need, but in far less time.

The desire to compete doesn't fade as gray hair appears, he says.

"At a masters meet," says O'Brien, who is head coach of a masters swim team in Walnut Creek, Calif., "you'll see guys who are in their 50s and 60s getting nervous in the blocks; they're very goal-oriented. And they're spending $200 and $300 for suits that make them a second faster."

But how they handle defeat, an unavoidable part of any athletic pursuit, does change. "What you'll never see at a masters competition is devastation and disappointment," he says. "They have goals, but if they don't achieve them, so what? It's part of life. They have other things that are important to them."

To be competitive, or at least be able to have the staying power to finish a game or a race, athletes should maintain a consistent exercise regimen that includes cardiovascular exercise, strength training and stretching. Starting a fitness regimen early, in one's 20s or 30s, goes a long way in ensuring that 10-kilometer runs, mountain climbs, hockey games and even ultramarathons are possible as the years go by. Even starting in one's 40s or 50s, or older, can lead to major fitness accomplishments.

Although 40 marks the age at which most men begin to lose about 1 percent of muscle mass per year, that can be circumvented by hitting the weights. And Nelson thinks that a good cardio program can help counteract the slow decrease in aerobic capacity over the decades.

Women might have an edge over men because they produce more estrogen, which helps protect the muscle cell membranes from wear and tear, says Robert Wiswell, an exercise physiologist and associate professor in the division of biokinesiology and physical therapy at the University of Southern California. "It may be a factor in allowing women to reduce the damage that is produced in loading, particularly in downhill running," he says. The fact that women generally weigh less than men might give them an additional advantage, because that lighter load creates less stress on the body.

Bon says she thinks a combination of factors has figured into her success as an endurance runner. She's run since high school, but only in the past four years has she explored ultra-races of 50 kilometers and more, racking up 25 so far.

She attributes the win at Angeles Crest (where she placed eighth in a field of 89 finishers), and her overall performance (she's shaved 40 minutes off her time in 100-kilometer races), to a solid athletic base, a healthy diet and a supportive family that doesn't balk when she goes on 60-plus-mile workout runs.

"I've learned to pace myself," says the stay-at-home mom from Sonoma, Calif. "And I've learned to mind my own race as opposed to my competitors' races." Life experience factors in as well: "I've been through three pregnancies, so I know I can endure a certain amount of discomfort. I lived in Central America and was a Peace Corps volunteer and lived through precarious situations."

Bon says she feels better and stronger now than she did in her 20s, and she is more in tune with her body, with no aches and pains from racking up the mileage. She doesn't think she's that unusual.

"There is such a depth of strength that is untapped, especially for women in their late 30s and 40s," she says. "I have a lot of friends who look at me and say, 'I could never do that.' But if you have the desire and the support, you really could. The potential is limitless."

Not every 60-year-old has to run a marathon, but it is possible to achieve lofty fitness goals.

"I firmly believe," Nelson says, "that we have underestimated as a culture, and maybe even in the field of exercise science, what older adults are capable of doing. It's really important for people to realize that you should not underestimate what someone can do based on age, gender or chronic disease."

Crittenden, who lives in Piedmont, Calif., and is an attorney for Oracle Corp., says her dedication to swimming won't be short-lived.

"Masters is for the long haul," she says. "They want you to be swimming when you're 70."