This is not your summer camp obstacle race: Elite athletes test strength, endurance at world championships

Hundreds of spandex-clad competitors are slogging uphill in the autumn mud, lugging two nine-kilogramsacks of sand.

This is the Obstacle Course Racing World Championships at the Blue Mountain Resort near Collingwood, Ont., a gruellingtest of strength and endurance that takes place this weekend.

The uphill bag carry is called the yoke walk, one of 34 obstacles placed around the mountain on a 15-kilometre course.

The other obstacles include a high curved wall, a floating net wall hanging from scaffolding,and la gaffe, a complicated apparatus of swinging poles created by Quebec racers.

Top athletes from around the world

The competition's spokesperson Margaret Schlachter says the competitors who have come to Blue Mountain, a popular ski resort about 160 km north of Toronto,are top finishers from obstacle course races across the globe.

"We have 67 nations here right now. All of the athletes have qualified to be here.These are the best of the best from around the world," she said.

There are 4,000competitors at the world championships, a testament to the growing popularity of obstacle course racing.

Matt B. Davis, who covers the obstacle course industry with his blog and podcast called Obstacle Racing Media,says what was an obscure pastime for adventurous athletes just five years ago has become mainstream.

"When I first started talking to people about this, they had no idea what I was talking about," says Davis, himself a racer."Now, if I meet somebody on a plane and I explain what it is that I do, it might take a minute, but then they say, 'Oh yes, my brother does those. My cousin does those.'"

Obstacle courses a growing business

Obstacle course races have become big business. Events with names like the Spartan Run, Tough Mudder and the Green Beret Challenge have become brandsin cities aroundthe world.

Obstacle course racing can also be quite lucrative for elite competitors.

Canadians Ryan Atkins and Lindsay Webster met on the competitive mountain bikecircuit five years ago. Since then, they have married, but have alsofallen in love with obstacle course racing.

"It just almost feels like it is catered to us," says Webster, 27. "Just having that upper body strength as well as the use of your cardio systems.As soon as we tried it, we were both, 'Yeah, this is something that we really like,' and it definitely challenges your full body."

Living on the winnings

Within a couple of years of competing, Webster rose to become world champion in both the three-kilometre and 15-kilometre course. Atkins is themen's world champ in the short course.

Theylive off their winnings at the dozen or so races they compete in each year. Top prize money is typically about $10,000, usually in U.S. dollars.

"If six years ago you would have told me I'd be in this position, I would have laughed," says Atkins, 30. "But here we are, and it's an incredible opportunity and we are blessed to have it."

Atkins and Webster abandoned mountain biking for obstacle racing and that has sincebecome an Olympic sport, with all the respect that brings.

While many of the competitors at the OCR World Championships are elite, well-trained athletes, obstacle racing can still bethe kind of thing coworkers might do as a charity challenge, ending with drinks at a pub.

"It's alwaysbeen this sort of two-track thing: Are we this sport, or are we this weekend fun thing?" says Davis.

A sport with Olympic aspirations

He says that may be settled by obstacle racing's Olympic aspirations. Many racers were hoping to see obstacle racing included at the 2020 games in Tokyo. But it was not on the list when the International Olympic Committee announced events for the Games in June,

"We are still a really young sport," Davis says. "Five years is nothing, when you think about how long triathlon has been around."

Triathlons had been held for about 25 years before they were included at the 2000 Olympic Games in Sydney.

For now, the millions of competitors in the more than 2,000 annual races worldwide are likely thinking less about obstacles to the Olympics and more about the physical challengesthey face on the race course.