Shoveling your way out of a snowstorm is actually a big workout. And that means that shoveling large amounts of heavy, wet snow—such as the snowfall currently descending on the Northeast—can pose significant health risks, particularly with heart and back strain.

Cardiologists say shoveling snow places a significant burden on the heart, increasing the heart rate and blood pressure. It is potentially risky, especially for people who don’t regularly exercise.

“For those at risk for heart disease and those that may not know they are at risk, shoveling snow can lead to or even cause a heart attack,” said Clyde Yancy, chief of cardiology at Northwestern University Feinberg School of Medicine in Chicago.

People without cardiovascular issues can safely shovel, but should try to reduce their efforts to about 80% of capacity, said Dr. Yancy. “Dial back your efforts about 20%, give yourself a break when you’re doing it and allow frequent stops.”

Avoid eating a heavy meal 30 to 60 minutes before or after shoveling as that places an extra load on the heart, Dr. Yancy said.