Updated

Want to live longer? Start exercising regularly and melt fat away. An hour of exercise can improve fitness, but losing body fat staves off the deadly metabolic syndrome, according to new research.

The study appears in the current American Journal of Preventive Medicine.

High blood pressure, high cholesterol, elevated blood sugar, and excess belly fat are the mix of risk factors known as metabolic syndrome (search). This cluster of risk factors increases the risk for heart disease, diabetes, and early death.

Exercise has been recommended to reduce a variety of these risk factors. Studies have shown that exercise works to reduce body fat, especially fat around the waistline, which is one of the risk factors for the metabolic syndrome. It also helps with heart disease factors like high blood pressure and high cholesterol. But this current study looks at the broader effects of regular exercise on this mix.

The study involved 115 people aged 55 to 75. All had untreated high blood pressure; 42 percent already had metabolic syndrome.

“The participants, in many ways, represent the ‘typical’ older American with mild [high blood pressure], many of whom are overweight, and at risk for [heart disease] and diabetes,” writes lead researcher Kerry J. Stewart, EdD, a cardiology researcher at Johns Hopkins School of Medicine.

Half were assigned a six-month moderate-intensity exercise program about one hour long, three days a week. However, they stuck with their regular eating habits.

The exercise regimen:

—A short stretching warm-up

—Two sets of resistance training (like hand weights), 10 to 15 repetitions each

—45 minutes of aerobic exercise, using a treadmill, stationary cycle, or stair machine

As fitness improved, the exercise intensity was increased to keep heart rate at target levels.

The participants also were measured for aerobic fitness, muscle fitness, and body composition.

Metabolic Syndrome Backs Off

Six months later, all volunteers had numerous tests for signs of metabolic syndrome. “Exercise training ... increased aerobic and strength fitness, reduced total and abdominal obesity, and increased lean body mass” for men and women alike, writes Stewart.

The exercisers’ risk factors improved, whereas those of the comparison group didn’t, he says. The exercisers lost more body and waistline fat and gained more muscle than the comparison group. Heart disease risk factors, like high blood pressure and cholesterol, also improved more in the exercisers.

After six months, 18 percent of exercisers and 15 percent of the comparison group no longer had metabolic syndrome. However, 8 percent of volunteers in the comparison group had developed the syndrome, Stewart reports.

“Older people can benefit greatly from exercise, especially to reduce their risk for developing metabolic syndrome,” says Stewart in a news release. “Our results show that this population can be motivated to follow through with a moderate exercise program, and for some risk factors, such as abdominal fat, exercise can be as effective as what is accomplished today with drugs.”

Other examples of moderate-intensity activities include walking briskly, recreational swimming, or bicycling 5-9 miles per hour on level terrain.

By Jeanie Lerche Davis, reviewed by Brunilda Nazario, MD

SOURCE: Stewart, K. American Journal of Preventive Medicine, Dec. 30, 2004.