The average life expectancy in the United States is currently estimated at 78.2 years.  That ranks us in 49th place in the world with 89.7 years enjoyed by citizens of Monaco, the global leader for longevity. The US also lags significantly behind Japan (82.2 years), Singapore (82.1),  Australia (81.8), and Italy (81 years). According to many doctors, we have no one to blame for this unimpressive statistic but ourselves. In a 2010 Harvard School of Public Health study, researchers identified four specific risk factors currently shortening lives in the United States.

The good news is that all four can be strongly influenced by your lifestyle choices, particularly your levels of physical activity. Experts are virtually unanimous in declaring that exercise (with its dramatic, measurable effects on health and longevity ) is the best anti-aging weapon in your arsenal.

Metabolic Syndrome

In addition to cigarette smoking, it is the unhealthy trifecta of high blood pressure, elevated blood glucose, and obesity that robs men of 4.9 years of life and women of 4.1 years. When these problems occur together, they are known as metabolic syndrome, a constellation of unhealthy conditions affecting 35 percent of all adults. Metabolic syndrome – which may also be attended by elevated triglyceride levels, decreased levels of healthy cholesterol, excessive abdominal fat and insulin resistance – can have devastating consequences.

The American Heart Association reports that people with metabolic syndrome are twice as likely to have a heart attack or stroke as people without the condition, as well as five times more likely to develop diabetes. A primary cause of metabolic syndrome is physical inactivity, although genetics may also play a role.

Age-Related Changes

Even for those who don’t develop metabolic syndrome, natural aging causes certain changes that take a toll on the body. For instance, your heart’s pumping ability drops 5 to 10 percent per decade. While a 25-year-old can pump 2 and 1/2 quarts of oxygen every minute, a 65-year-old’s heart only pumps 1 and 1/2 quarts in that interval. In addition, blood vessels begin to lose flexibility in middle age, causing blood pressure rates to creep up at a rate of about 6 points per decade.

Finally, most Americans gain 3 to 4 pounds a year after becoming middle-aged. Far from the muscle-packed weight gain seen in teens and young adults, this surplus weight is virtually all fat, which causes a rise in unhealthy LDL cholesterol as well as a decrease in desirable HDL cholesterol. Endurance exercise, performed 3 to 4 hours a week, is the gold standard for improving cardiovascular performance and boosting the body’s metabolism in older adults. This type of exercise decreases body fat, causes a desirable increase in the body’s sensitivity to insulin and reduces blood sugar levels and triglycerides.

As if this weren’t beneficial enough, adequate exercise improves cholesterol levels, causes more efficient digestion, and combats osteoporosis by increasing the calcium content of bones, A 10-year study of 650,000 adults conducted by the National Institutes of Health supports the premise that endurance exercise prolongs life. Researchers discovered that people who reported exercising either at moderate intensity for 2.5 hours a week or at vigorous intensity for 75 minutes a week, gained 3.4 years of life compared to those who were inactive.

The benefits seemed to accrue in approximate proportion to the amount of exercise. People who doubled the recommended level gained 4.2 years while those who got half the advised amount gained 1.8 years. It is not necessary for exercise to be strenuous in order to increase longevity and improve cardiovascular health. Harvard Health notes that health benefits are linked with relatively modest exercise levels. An exercise program consisting of 30 minutes of brisk walking can produce major benefits if performed on an almost daily basis. Jogging, biking, swimming, aerobic dancing, tennis, and racquetball are also good examples of endurance exercise.

The Bottom Line

Consult your doctor before beginning any exercise regime, especially if you have been inactive for some time. To avoid injury, start slowly, and invest in proper training and equipment if necessary.  No matter what your age or fitness level, exercise can help you fight the negative effects of aging.