Don't be surprised if you see a firefighter in full gear and a choir full of singing girls among the runners at the Calgary Marathon this spring.

It's all part of a plan to break several Guinness World Records during the 2016 race.

"There are some very ambitious runners in our community," said Kirsten Fleming, executive director of the Calgary Marathon Society.

Noel Darcy, a volunteer firefighter in Olds, Alta., will be attempting to run the full marathon (42.2 kilometres) wearing his boots, jacket, pants, hat and oxygen tank.

Kirsten Fleming Calgary Marathon

"There are some very ambitious runners in our community," said Kirsten Fleming, executive director of the Calgary Marathon Society. (Kirsten Fleming/Facebook)

"He has to break 3.41 and his personal best is 3.04, but that's without all the extra weight," she said.

The Calgary Girls Choir has already submitted a request to Guinness to establish a record for the most people singing while running in a five-kilometre race.

"They have youth on their side," Fleming said.

The girls will be fundraising for the Scotiabank Calgary Marathon Charity Challenge.

24-hour marathoners

A dozen men will be tag-teaming a treadmill run for 24 hours during the marathon's Health and Wellness Expo in the Big Four building.

Their goal is to run 350 kilometres for MitoCanada, which supports families impacted by mitochondrial disease.

"They're going to be running through the night, two [in the morning] so you might want to come down and bring them some coffee," said Fleming.

Calgary ultramarathoner Dave Proctor will also take on a similar challenge — except he's doing it solo. Proctor will be trying to run 258-kilometre non-stop on a treadmill in one day.

Dave Proctor ultramarathoner

On May 29, ultramarathoner Dave Proctor will try to run 258 kilometres in one day on a treadmill. (Dave Proctor/Facebook)