It's a well-known fact that strenuous activity increases blood pressure. A study of healthy but inactive men, with an average age of 32, found that most of them experienced heart rates that exceeded the upper limits prescribed for aerobic training after shoveling heavy, wet snow in the cold. None of them had heart disease or high blood pressure.

News reports after snowstorms frequently include reports of heart attacks in middle-aged and older people clearing their driveways and sidewalks. If you have high blood pressure, experts advise that you should be very cautious about shoveling snow. It's a good idea to wear a breathing mask or a scarf over your nose and mouth to avoid inhaling cold air, which can cause the coronary arteries to narrow. Take it easy – start gradually and avoid sudden exertion. Lift modest amounts of snow at a time, and take frequent breaks.

Even better – invest in a motorized snow blower, or hire a neighborhood kid to do the shoveling.

Sources: Franklin BA, Hogan P, Bonzheim K et al. Cardiac demands of heavy snow shoveling. JAMA 1995;273(11):880-2.

Franklin BA, et al. Exercise for persons with cardiovascular disease, in Current Comment, from the American College of Sports Medicine, July 1998.