THURSDAY, Dec. 15 (HealthDay News) -- Snow shoveling does increase the risk of heart attack, a new study confirms.

While many people believe this, there has been little actual evidence, according to researchers at Queen's University in Kingston, Canada. So they decided to look for proof.

They reviewed the records of 500 patients who went to Kingston General Hospital with heart problems over two winter seasons. Of those patients, 35 (7 percent) started experiencing heart symptoms while shoveling snow.

"That is a huge number," Dr. Adrian Baranchuk, a professor in Queen's School of Medicine and a cardiologist at Kingston General Hospital, said in a university news release.

"Seven percent of anything in medicine is a significant proportion. Also, if we take into account that we may have missed some patients who did not mention that they were shoveling snow around the time that the episode occurred, that number could easily double," he explained.

The researchers also identified three main factors that put people at high risk for heart problems while shoveling snow: being male (31 patients); having a family history of premature coronary artery disease (20 patients); and smoking (16 patients).

They also found that regularly taking four or more cardiac medications could lower the risk.

The study was recently published online in the journal Clinical Research in Cardiology.

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