Hamilton’s running community is in shock Monday after the death of an avid runner at yesterday’s Road2Hope Marathon, but a McMaster heart doctor says running can still be worth the risk.

The man, whose identity hasn’t been shared at the request of his wife, who also raced on Sunday, was described by store staff at the Runner’s Den as an avid, fast runner who had previously qualified for the Boston Marathon. He was in his mid-50s and just 10 metres from the half-marathon finish line when he collapsed.

"All the runners here are so upset," said the Running Den’s Esther Pauls, who is also one of the Road2Hope co-ordinators.

There’s nothing in life that brings things down to zero risk. - Dr. Robert McKelvie, Hamilton Health Sciences cardiologist

An emergency crew that included physicians, nurses, paramedics and first aid responders immediately performed CPR on the man, but he was pronounced dead in hospital. It’s unclear what caused him to collapse, but in most marathon deaths cardiac arrest — the deadly condition when the heart stops beating — is to blame.

Dr. Robert McKelvie, a cardiologist with Hamilton Health Sciences and McMaster professor who specializes in heart failure, physiology and exercise testing, said it’s possible an underlying heart condition likely caused the runner’s collapse.

"A lot of these guys that are avid runners … may not have been as physically active for their entire life," McKelvie said, noting disease starts accumulating in the coronary arteries in your 20s.

"Most times with people in this age group, it’s usually coronary disease that’s the culprit."

McKelvie said it’s a good idea to get checked out by a doctor before embarking on a running program.

But, the scary thing for runners, is that these "occult" heart diseases, as McKelvie calls them, don’t necessarily impair a runner’s performance or even present symptoms. He recalls treating an Around The Bay running race competitor who raced to a fast time and then collapsed in his office two days later.

Overall, being physically fit reduces the risk of heart disease. But it can’t stop tragedies like Sunday from happening.

"There’s nothing in life that brings things down to zero risk," McKelvie said.

Male runners at greater risk: study

Among runners and race organizers, the risk of cardiac arrest is known but marathon deaths are still shocking. At last year’s Road2Hope a runner collapsed near the Confederation Park finish line, while multiple runners have died over the years at major marathons like Toronto, New York and Chicago.

The RACER study, a widely-cited 2012 report in the New England Journal of Medicine, laid out perhaps the best analysis of cardiac arrest in long-distance running races.

The study found there were 59 cases of cardiac arrest (40 in the full marathon and 19 in half-marathons) among the 10.9 million registrants in U.S. races from 2000-2010. That's one cardiac arrest per 184,000 racers. Of those who suffered cardiac arrests, 42 died.

Men were far more likely to suffer cardiac arrests than women, while the average age was 42-years-old.

The incidences of cardiac arrest, the study found, spiked in the fourth quarter of the race. The study also found that late into races fewer people were able to survive a cardiac arrest.

According to Heart and Stoke Canada, there are up to 40,000 cardiac arrests each year in Canada — one every 12 minutes — most of which result in death.