Dr. Chris Milburn, a long-distance runner who practises at the Cape Breton Regional Hospital in Sydney, said Monday he knew 18-year-old Emma van Nostrand through the running club he leads — the Cape Breton Road Runners.
Van Nostrand, an honour student in Grade 12 at Riverview High School in Coxheath, N.S., was running in the Toronto Marathon on Sunday when she collapsed within three kilometres of the finish line.
Milburn said it's unclear what happened and an autopsy is pending.
"(But) it's important for people to know how incredibly rare it is so people don't become afraid of getting off their couch," said Milburn, who also works in sports medicine.
"Whatever the risk is, it's minute compared to the risk of staying on the couch too much. That's what most of us die from in North America: sedentary activity."
And it would be wrong to think this kind of tragedy is peculiar to those who run marathons, he said.
"It's an idiosyncratic thing," Milburn added.
"A lot of time it has something to do with an in-born defect of the heart that no one knew about. ... I hope people don't come away from this thinking she somehow shouldn't have been allowed to run the marathon, or that marathons are bad for young people."
Milburn said the young woman was in good shape and had recently completed her first 21-kilometre half-marathon.
"She had been working up and was doing very well," he said in an interview.
Van Nostrand's parents, Steven and Katherine, also competed in the race, Milburn said.
"It's very tragic," he said. "I've worked as an ER doctor for about 14 years and this is easily one of the worst things I've had to deal with."
A crisis intervention team has been sent to the high school where van Nostrand was a student.
Joe Chisholm, principal of Riverview High School, said van Nostrand had planned to go to university in the fall.
"She was very much an independent, free spirit," Chisholm said.
Aside from running, van Nostrand played soccer and basketball for the school. And last fall, she went to France, where she studied French while keeping up with her regular school work through correspondence.
"She was a tremendous student and a lot of the other students looked up to her as a leader," said Chisholm.
"A lot of the students are having a tough day and they're leaning on their teachers to talk about this tragedy. ... The students are quite quiet and quite shocked about the whole thing. It's like everybody is numbed by it."
Chisholm said van Nostrand's father had recently spoken to local media about completing his seventh Boston marathon on April 18, recounting the terrorist bombings that killed three people and injured more than 250.
— By Michael MacDonald in Halifax