Blurring the lines between fitness and survival, the Run For Your Lives 5K race gives you a reason to run like hell — or from it.

On Saturday, approximately 3,000 runners, spectators and, yes, zombies, will head north of Toronto to the ‘Infected Zone’ in Oro for a unique twist on the adventure race.

Competitors run a 5-kilometre obstacle course over hay bails, mud slides and even a blood pit, while being chased by participants dressed up as zombies. Each runner has three “health flags” on a belt around their waist and need at least one at the finish line to finish alive.

“It is a really weird concept isn’t it?” laughed event co-ordinator Olivia Orth. But who would pay $87 (U.S.) to be chased?

“I think it’s people who want a change. We’re used to seeing [other adventure races like] the Warrior Dash and the Tough Mudder, but there’s no element other than the obstacles,” Orth said.

The solution, naturally, was to add zombies. The undead arrive alive hours before and pay $25 for a full zombie transformation including wardrobe and fake blood.

The idea to add zombies in an adventure race came while co-founders Derrick Smith and Ryan Hogan were on the couch watching AMC ’s The Walking Dead.

Hogan was looking for a way to promote his athletic gear company with the tag line “run for your lives.” With the addition of zombies in chase and Hogan’s bare-bones staff of seven, they hosted the first race outside of Baltimore in October 2011.

What they didn’t expect were the nearly 12,000 people that showed up.

Since then, the popularity of the race has grown with almost 85,000 runners and zombies expected to compete in 12 races across North America this year.

And it’s drawing unlikely competitors, like Jeffy Parsons-Sheldrake, a family doctor in Kingston whose treadmill-time depends on the length of the T.V. show he’s watching.

“I think the idea that people will chase you is part of the draw,” said Parsons-Sheldrake. “It’s the zombie motif that I think is going to be fun and hilarious.”

The physician added, anything that gets people out training is a good thing and that, at just five kilometres, “Anyone can do this as long as they’re not averse to getting a little dirty.”

That being said, Parsons-Sheldrake received an email from organizers about the possibility of electric voltage somewhere on the course.

Orth wouldn’t give any details on what competitors could expect — videos online show competitors crawling under an electrically-charged fence — adding the surprise is half the fun.

“We want people to be dipping and dodging from the zombies,” Orth said.

The race donates a portion of the profits to the American Red Cross. The first wave of runners hits the course at 9 a.m., with the last at 4:30 p.m. Registration closed Tuesday, but spectator tickets which include live bands, beer tents and the option to camp overnight are still available, starting at $32.