Race director Jay Glassman says organizers have heard from dozens of runners who weren't planning to join the race prior to the Boston attacks last month, but are now rushing to participate on Sunday along with an expected 12,000 others.
He says there will be a minute of silence for the Boston victims before the full marathon, half-marathon, 5 kilometre and relay runs begin.
Runners will also bear a small visual reminder of the Boston attacks, with event bibs featuring a toonie-sized "Remember Boston" ribbon image.
Glassman says special "Boston: we run with you" T-shirts will also be sold at the pre-race expo, with proceeds going to the Boston Children's Hospital.
The bombings that killed three people and injured more than 260 others have brought together runners around the globe, with many Canadian cities seeing informal solidarity runs held in the days after the April 15 attacks.
Glassman said it is also anticipated that the Toronto race — a qualifier for the Boston Marathon — will draw a bigger crowd of spectators than last year, with more people expected to huddle along the midtown-to-downtown and shorter lakeshore routes.
"We've heard from a lot of people in the community, both runners and spectators alike, who said — almost in defiance of what happened in Boston — that if they couldn't run they'd be out there to support those who will be running."
"We've also had people come (to register) who weren't necessarily training or planning to run this event, but because of what happened many have decided to run," he said.
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