WEDNESDAY, March 13, 2002 (HealthDayNews) -- Want to know your risk of dying? Hop on a treadmill and start walking. The longer you can walk, the lower your risk.
Want to reduce your risk of dying? Exercise to improve your treadmill performance. Every minute you add will decrease the risk by at least 8 percent, and probably more.
Indeed, exercise capacity -- as measured by treadmill performance -- is the best single predictor of mortality, better than high blood pressure, smoking, diabetes and sophisticated tests of heart function, says a report in tomorrow's New England Journal of Medicine. That's true not only for people with known heart problems, but also for healthy individuals.
The finding comes from a six-year study of more than 6,000 men, whose average age was 59, who were referred by their doctors for treadmill exercise testing. During the study, 1,256 of the men died, an average annual mortality rate of 12.9 percent.
"After adjustment for age, the peak exercise capacity, measured in metabolic equivalents (MET), was the strongest predictor of the risk of death among both normal subjects and those with cardiovascular disease," the report says. Jonathan Myers of the Veterans Affairs Palo Alto Health Center in California led the study.
MET is the unit used to measure physical fitness. One MET is roughly equal to one minute of treadmill time, the researchers explain. The fittest men in the study had a MET of 10 or higher. The relative risk of death for men with the lowest MET, 5 or under, was four times greater than for men with the highest MET scores, 8 or higher, the study found.
The results confirm earlier studies, which have shown that every 1-MET increase in exercise capacity after training reduces the risk of death by 8 percent to 14 percent, the researchers say.
The new study is more confirmation of what physicians have long known, says Dr. Richard A. Stein, chief of cardiology at the Brooklyn Medical Center.
"Any marker of overall exercise capability has always been a prime indicator of clinical outcomes in humans," Stein says. "Physical ability integrates a whole variety of characteristics -- how well the heart pumps blood, how well the arteries expand to allow blood flow, and more."
One important aspect of the study is that it examines groups of people
with specific risk factors, says Dr. Gary J. Balady, professor of medicine at
Boston University Medical Center.
"They looked at people with known cardiovascular disease and found the same results," says Balady, who wrote an editorial accompanying the study. "Then they did another subgroup analysis relative to risk factors such as diabetes, high blood pressure, obesity and smoking and found the same results. For each group, fitness is an important predictor of survival. This brings to the forefront the whole issue of fitness."
What To Do
"It's important for people to know that if they do poorly on a
fitness test, they are not doomed," says Balady. "They can change their
outlook by beginning an exercise program. Several studies have shown that you can improve your fitness and reduce subsequent mortality."
Read about exercise and longevity.
You can get an overview of the benefits of exercise from the American Heart Association.
