What are they thinking? Runners line up to tackle Calgary's 150-km ultra marathon

Calgary marathon organizers wanted to up their game this year, so in honour of Canada's 150th anniversary, they added a 150-kilometre ultra marathon to their existing races.

That's roughly the distance from Calgary to Red Deer.

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But what goes through the mind of a runner to mentally prepare for such a gruelling endeavor?

We asked four runners and here's what they said:

Martin Parnell of Cochrane, Alta.

"I chunk it down. I break it down into little pieces," Martin Parnell told CBC News.

"I chunk it down into 10-minute pieces. I run for nine minutes and walk for one. I don't try and get ahead of myself, I don't even worry about that. Just get through the next nine minutes of running and then start walking. I walk to give my legs a rest but also to take in my nutrition, hydration and electrolytes."

Jenny Lynn of Sudbury, Ont.

"It's just the challenge to see if you can actually finish it. It takes a toll so you have to find that mental state to keep pushing through," Jenny Lynn explained

"I believe, I believe, I believe, I believe, over and over. I think of all of my friends who keep telling me that 'You can do this,' I don't want to let them down because they believe so much in me that I just keep pushing through."

Beverley Grobbelaar of Calgary

"I am not a great trainer, unfortunately, I don't put in what I should, but I think my mind is strong enough to get me through it," Beverley Grobbelaar said.

"I love to run and I am just going to keep reminding myself of that and I have the ability to do it. When I am having a really low moment, I often think of people that would like to run or can't run and that gets me through it."

Noel D'arcy from Olds, Alta.

"There is a lot of motivation and energy from the crowd and from the cheering. There is a lot of support out there," Noel D'arcy said.

"I will be visualizing the finish line because it's what keeps me motivated to keep going. I can't explain the feeling when you finish a long distance race. It's something that is pretty incredible."