WEDNESDAY, Oct. 5, 2011 (HealthDay News) -- Three hours of vigorous exercise a week can reduce a man's heart attack risk by 22 percent, a new study suggests.
The Harvard School of Public Health researchers also found that about 38 percent of that decreased risk was due to the beneficial effects of exercise on a man's levels of "good" high-density lipoprotein (HDL) cholesterol.
The findings were published Oct. 4 the journal Medicine & Science in Sports & Exercise.
The study included 1,239 men in the Health Professionals Follow-Up Study who provided information on their weekly amount of exercise. The researchers also analyzed the men's cholesterol levels, as well as biomarkers of inflammation and insulin sensitivity.
Between 1994 and 2004, 454 of the men suffered a nonfatal heart attack or died from coronary artery disease. Of these, 412 men were compared to a control group of 827 men without heart problems.
"As expected, traditional cardiovascular disease risk factors were more common among cases than controls," study author Andrea Chomistek said in a journal news release. "Men who suffered a nonfatal heart attack or died from coronary heart disease had less 'good' cholesterol, more 'bad' [LDL] cholesterol and were more likely to have high blood pressure, high cholesterol and diabetes."
The U.S. National Heart, Lung, and Blood Institute has more about physical activity and your heart.