The last time the D.C. area had a blizzard, at least three people shoveling snow had heart attacks and died.

So doctors are urging all of us to take it easy.

Shoveling six to eight inches of heavy, wet snow requires a plan. Doctors say it can burn more energy than a full throttle run. All that shoving, and lifting and tossing can strain even a healthy heart.

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"You have to be careful. You don't normally stress your heart suddenly like this," said Sibley Hospital Medical Director Larry Ramunno, Md. He fears he'll see an influx of even more patients this year than usual. "That's the problem. You haven't been shoveling all year, and all of a sudden, you've got a lot of snow on your shovel. And of course you want to get it done because you want to get out."

But what you don't want, is to have to get out in the back of an ambulance. In last January's blizzard, a fit, 44-year-old US Capitol Police officer, Vernon Alston, died while shoveling his driveway.

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"Short snippets of work," advises Dr. Ramunno. "Fifteen to 20 minutes. If we get six to eight inches, don't take them all. Take them in layers and takes breaks in between, because people are not ready to lift his kind of snow."

Sometimes the symptoms of a heart attack are not what you think. Dr. Ramunno says you should know the warning signs.

"That could be chest pain, but it frequently is nausea or lightheadedness, or just energized weakness, particularly in women, where chest pain is less common."

Here are some other tips from cardiologists: Don't run out the door and start shoveling as soon as you wake up. Heart attacks often occur in the morning, when blood is more prone to clotting. Drink plenty of fluid to keep yourself hydrated. And don't eat a huge meal before shoveling. That's actually been shown to increase the risk of cardiac injury.

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