According to the Bible, Methuselah lived to the ripe old age of 969. The modern record for longevity is held by Jeanne Calment of Arles, France. Born Feb. 21, 1875, she died 122 years and five months later in August 1997.

The average life expectancy for American men born in 2005 is 75.2 years, 80.4 for women, according the Center for Disease Control. So few of us can expect to live nearly as long as Ms. Calment did. But if we follow the advice and example of two prominent physicians at the University of Pittsburgh Medical Center, we could expect to add 10 to 15 years to the average life span.

Dr. Joseph Maroon, 68, is vice chairman of neurological surgery at UPMC, the team neurosurgeon for the Steelers, and a triathlete who has completed the Ironman in Hawaii (2.4-mile ocean swim, 112-mile bike ride, 26.2-mile run) twice, most recently last October.

Dr. Vonda Wright is an orthopedic surgeon and the director of PRIMA (the Performance and Research Initiative for Masters Athletes at UPMC's Center for Sports Medicine). She's run the Chicago Marathon three times, and competes frequently in shorter races.

Dr. Maroon and Dr. Wright have written books describing how we can live longer -- or at least healthier -- lives. In "The Longevity Factor," Dr. Maroon explains how substances in certain foods trigger a specific set of genes in humans that make us healthier and cause us to live longer. "In Fitness After 40," Dr. Wright explains why exercise is so important for warding off disease, describes simple exercises that anyone can do at home without special equipment, and has special advice for arthritis sufferers.

About 30 percent of longevity is determined by our genetic makeup, and we are genetically programmed to wear out after a time, Dr. Maroon said. But about 70 percent of what we regard as aging is determined by our eating and exercise habits.

"The foods we eat or don't eat, the exercise we engage in or avoid, and the decision to use or abstain from addictive substances are critical in determining our life span," he said.

"Physical inactivity is a serious health threat and will lead to premature disability or death in more than 2.5 million Americans in the next 10 years," Dr. Wright said. "There are 35 common diseases that are made worse if people are physically inactive, including diabetes, high blood pressure, heart disease and stroke.

"Your body will change because of the biology of aging, but without the devastating factor of disuse, we are capable of remaining amazingly fast and functional as we age," Dr. Wright said. "Many of the changes popularly associated with aging are less the result of biology and more the result of the lifestyle choices you make as you grow older."

A few good habits can overcome some bad ones. Ms. Calment attributed her long life and good health to her habit of taking long walks virtually every day, and drinking a glass or two of red wine each night. She rode a bicycle until she was 100.

But Ms. Calment also smoked until she was 117, and consumed two pounds of chocolate a week.

Dr. Maroon discusses the "French paradox" in his book. The French consume considerably more fat in their diets than we do, yet suffer heart attacks at half the rates Americans do, and have far fewer obese people.

The right kind of chocolate (in smaller amounts than Ms. Calment consumed) can be good for you, Dr. Maroon said. But what was especially beneficial was the red wine. It contains a substance called resveratrol, which triggers genes in humans which promote survival. His research has led him to drink a glass or two of red wine each day. But the limit should be two glasses for the typical man, one for the typical woman, he cautioned. If you drink more than that, the detrimental effects of the alcohol overwhelm the beneficial effects of resveratrol.

Pinot noir is the best source of resveratrol, Dr. Maroon said, but other red wines also contain the substance. Abstainers from alcohol can get a more modest benefit from drinking grape juice.

Other foods that trigger life-enhancing responses in our genes are green tea, and dark chocolate (more than 70 percent cocoa, no added milk), he said.

But "you can eat all the right things and still be fat," Dr. Wright said. "To become more fit and control chronic disease, we need to take 10,000 steps a day."

That translates into about five miles of activity. But the typical sedentary person usually covers only between 1,000 and 3,000 steps between his house, car, workplace, errands, and so forth. Dr. Wright recommends you buy a pedometer, find out how many steps you take in a typical day, and figure out ways to increase that number.

But even if you start walking up the stairs instead of taking the elevator at work, and take a stroll around the neighborhood in the evening, the typical person will still need about 30 minutes of aerobic exercise a day to get to 10,000 steps.

The benefits can be considerable. A study at the University of Tennessee indicated women who averaged more than 10,000 steps a day had 40 percent less body fat than those who averaged less than 6,000 steps a day.

If you follow the advice in the books by Dr. Maroon and Dr. Wright, you'll probably live longer, and you'll certainly live better.

"We're talking about the compression of morbidity," Dr. Maroon said. "We want you to live well, long, and to die quickly."

Both books were published this month and can be purchased from Amazon.com. "The Longevity Factor" costs $17.82, "Fitness after 40" costs $17.95. Both also should be available at area book stores.