When It Comes to Exercise, the More, the Better
Oct. 22, 2002 -- Regular exercise is key to maintaining a healthy heart, but how much do you need and what kind? New research suggests that the more vigorous the exercise the better, and that combining aerobics and weight training is the best approach for reducing heart disease risk.
Harvard University School of Public Health researchers followed close to 45,000 men to see how exercise habits affected their risk of heart disease. The findings are reported in the Oct. 23/30 issue of TheJournal of the American Medical Association.
Men who ran for at least an hour each week had a 42% reduced risk for developing heart disease and dying. Lifting weights for 30 minutes or more per week cut the risk 23%, while rowing an hour or more per week cut the risk by about 18%.
Even walking briskly each day for at least 30 minutes led to an 18% reduction in heart disease risk. And the faster the men walked, the more benefit they gained -- regardless of how long they walked. The protective effects of exercise were seen in all ages, and in men who were overweight or had a family history of heart disease.
"We found that the amount, intensity, and type of exercise are all important when it comes to reducing the risk of heart disease," researcher Frank Hu, MD, PhD, tells WebMD. "A take-home message is that the more the better when it comes to exercise, and that adding weight training to an aerobics routine may be most beneficial of all."
The study is one of the first to link weight training to a lowered risk of heart attack and death. Weight training does not directly improve heart function the way aerobic exercise does. Instead, Hu suggests it may reduce risk by increasing lean body mass, thereby improving insulin sensitivity. Poor insulin sensitivity has been linked to an increased risk for heart attack and diabetes.
Sedentary people can reduce their risk of heart disease by increasing their amount and intensity of exercise from low to moderate, according to the researchers. Likewise, people who are already active can reduce their risk further by pumping up the intensity of their normal routine.