Why do so many people die shovelling snow? 19 November 2014 Last updated at 23:09 Who, What, Why The Magazine answers the questions behind the news At least two people have died from heart attacks while shovelling snow in Buffalo, New York. Every winter, about 100 people in the US die doing this. A study looking at data from 1990 to 2006 by researchers at the US Nationwide Children's Hospital recorded 1,647 fatalities from cardiac-related injuries associated with shovelling snow. In Canada, these deaths make the news every winter. Cardiologist Barry Franklin, an expert in the hazardous effects of snow removal, believes the number of deaths could be double that. "I believe we lose hundreds of people each year because of this activity," says Dr Franklin, director of preventative cardiology and cardiac rehabilitation at William Beaumont Hospital, Michigan. His team found that when healthy young men shovelled snow, their heart rate and blood pressure increased more than when they exercised on a treadmill. "Combined this with cold air which causes arteries to constrict and decrease blood supply, you have a perfect storm for a heart attack," he says. raises blood pressure and heart rate more than normal exercise cold air constricts blood vessels it's an early morning activity when cardiac Snow shovelling is particularly strenuous because it uses arm work, which is more taxing than leg work, and means the shoveller has to stand upright thus diverting blood away from their heart to their lower limbs. They also have to strain against the snow, especially if it is wet and heavy, causing a further increase in heart rate and blood pressure. Many people hold their breath during the hard work, which also puts a strain on the body. To add to this, the prime time for snow clearance is between 6am and 10am which is when circadian fluctuations make us more vulnerable to heart attacks. Dr Franklin considers snow shovelling to be so dangerous that he advises anyone over the age of 55 not to do it. "People at greatest risk are those who are habitually sedentary with known or suspected coronary disease who go out once a year to clear snow," he says, adding smoking and being overweight drastically increase the risk. If you must do it, push rather than lift the snow, dress in layers, take regular breaks indoors and don't eat or smoke before shovelling," he says. Using a snow blower is a better option, but Dr Franklin says he has also recorded heart attacks in men using blowers. "People don't have any idea how taxing it is on the heart," he says.