Exercise Cuts Heart, Diabetes Risk Factors
Program reduces incidence of metabolic syndrome
WEDNESDAY, Dec. 29, 2004 (HealthDayNews) -- Regular exercise can reduce the incidence of a deadly combination of risk factors for heart disease and diabetes in middle-aged and older people.
A six-month program of aerobic exercise and weightlifting lowered the rate of this combination, called metabolic syndrome, by 41 percent in 104 people aged 55 to 75, according to a report in the January issue of the American Journal of Preventive Medicine.
Metabolic syndrome is defined as having three or more of six major risk factors for cardiovascular disease: obesity, high blood cholesterol levels, high blood pressure, high blood sugar readings, a tendency to form blood clots, and high blood levels of C-reactive protein, a marker of inflammation.
When the study began, 43 percent of participants had metabolic syndrome, although none had cardiovascular disease. Half were simply given a booklet that encouraged increased activity such as walking, while the others were assigned to a program of supervised exercises, three 60-minute sessions each week.
"We followed the guidelines of the American College of Sports Medicine," said study leader Kerry Stewart, a professor of medicine at Johns Hopkins University School of Medicine. "It was a combination of aerobic exercises such as walking, swimming and jogging, as well as weightlifting."
After six months, there were no new cases of metabolic syndrome in the exercise group, and nine of them no longer had the syndrome. While the syndrome was no longer present in eight of the people in the sedentary group who had it at the start, four new cases were diagnosed in that group.
While tests showed substantial improvement in fitness, such as peak oxygen uptake, "the changes in disease risk factors with exercise training were more closely related to reductions in body fat, particularly in abdominal fat, and increases in muscle tissue," Stewart said.
The kind of exercise program in the study can easily be done by anyone without supervision, he said. "You can do brisk walking or bicycling on your own," he said. "You can also work with things like hand-held weights at home."
The weightlifting part of the program had participants in a 20-minute session in which they did two sets of 12 to 15 lifts each, with weights tailored to individual ability.
"They did resistance exercises, which we now recommend for everyone," said Dr. Gerald Fletcher, a cardiologist at the Mayo Clinic in Jacksonville, Fla., and a spokesman for the American Heart Association. "Weightlifting, carefully done, is something we recommend more and more along with aerobic exercises."
But "carefully" is the keynote, especially for older and sedentary people, Fletcher said, because of the possibility of injury to unused muscles. Exercise programs are best when tailored to an individual's abilities, he said.
"Initially, it might be better to have someone teach you how to exercise," Fletcher said. "Getting a trainer might be worth it, or getting someone to give you a personalized exercise program."
A rundown on metabolic syndrome and what can be done about it is offered by the American Heart Association.