Shaun Stephens-Whale has run up mountains, around tracks and on treadmills.
But he found his niche in an activity that most Canadians think little about: climbing stairs.
The elite tower runner told CBC Radio's Metro Morning ahead of his race up the CN Tower on Sunday that no other sport "simulates the kind of pain you feel if you do it right."
Gripping the railings, taking the stairs two at a time, he's aiming to beat the standing CN Tower record — about 10 minutes — as part of an event to raise money for the World Wildlife Fund.
"I like the sense of accomplishment and the feeling of pushing your body to the limit," he said.
Stephens-Whale, also a member of Canada's national mountain running team, began training for tower running by using his staircase at home in British Columbia.
"One floor, up and down, 50 times as fast as I could," he said.
Now he uses office towers and condos in Vancouver as a training ground, finding buildings with between 500 and 1,200 steps and running them over and over.
One thing he won't do? Take the stairs down.
"It's an almost zero impact sport if you're going just up," he explained. He takes the elevator down to avoid soreness and protect his knees.
On Saturday, the public will climb the CN Tower for the event. On Sunday, more ambitious climbers like Stephens-Whale will step up to the plate for a timed race.
The key to winning? "Maintain a hard burn and push through," he said.
If the CN Tower's 1,776 steps don't seem like your cup of tea, Stephens-Whale still encourages people to give stairs a try.
"It is a great workout. Just start modestly, maybe with 10 floors, and work your way up from there."