The popular belief that shoveling snow can lead to cardiac arrest may be true, according to a new study published in the journal Clinical Research in Cardiology.

Researchers in Kingston, Canada, reviewed data of 500 patients with heart problems over a two-year period. They found that 7 percent experienced heart symptoms while they shoveled snow. Their average age was 63.

“That is a huge number,” said Dr. Adrian Baranchuk, a cardiologist at Kingston General Hospital. “Seven percent of anything in medicine is a significant proportion.”

Male smokers with a family history of early heart disease were the most likely to experience heart problems during this common winter chore, they found.

Taking cardiac medications may lower a person’s risk, researchers noted.