About 25,000 runners will be at the starting line in the Scotiabank Toronto Waterfront Marathon on Sunday, but just getting there will be a victory for Rob Burtch.

The 35-year-old with cystic fibrosis is on the waiting list for a double-lung transplant. He hopes to complete his five-kilometre walk — with his oxygen tank strapped to his back — in about an hour, while also raising awareness and donations for the Cystic Fibrosis Foundation.

Watch the video above as CBC News reporter Debbie Lightle-Quan has more on this inspiring story.

You can catch the Scotiabank Toronto Waterfront Marathon live Sunday at 8:15 a.m. ET on cbcports.ca.