Is the threat of a heart attack while shoveling snow an urban legend? Actually, it's very real and deadly. A 1996 New England Journal of Medicine study pointed out that these sudden heart attacks can strike people with no history of heart disease, and are more likely to occur in older people with otherwise sedentary lifestyles.
This particular chore is so deadly because of a combination of factors. First, the activity is strenuous—it can burn up to 200 calories in 30 minutes. Second, it is done in the cold which causes blood vessels and arteries to constrict and make a heart attack more likely.
The best ways to protect yourself are: