Whether they're climbing, running, rafting, mountain biking, or paddle boarding and dealing with brutal heat, cold or punishing topography, extreme sportsmen Simon Donato and Paul "Turbo" Trebilcock are up for the challenge. Their exploits are the basis of the Esquire Network series "Boundless," which returns for its 10-part second season on May 27 and takes them from Austria to Mongolia, the Amazon, and the Yukon to race in the world's toughest competitions. It takes a unique physical and mental strength to make it, as they explain here.

MNN: Where did the idea for "Boundless" originate?

Simon Donato: In 2010, I created an Adventure Science documentary called "Go Death Racer," which followed me and two other friends as we raced one of Canada's most well-known ultras. I had my university friend and Sigma Chi fraternity brother Josh Eady do the edit. He and I came up with the pitch, and the timing was good. It was picked up quickly. I met Paul around 2004 at a local orienteering race in Hamilton. He came up and started talking to me like we had known each other for a long time. I'd never met him before in my life. He scared me a bit, to be honest. 

What kind of background do you have in extreme sports, and what training do you have to do to prepare for these races? Do you follow a special diet as well?

Donato: When I was 18, I started a mountain bike center at my local ski hill, and at 21, I had competed in my first 36-hour adventure race. I've since done many of the biggest adventure races in the world. To be a good adventure racer means you have to be a jack-of-all-trades, so in training for "Boundless," I typically put in big mileage on road and mountain bikes, hit the trails to run, and spend time in the gym, and on my SUP [stand-up paddleboard]. Average weeks are 10-20 hours of training. For my diet, I choose to eat clean. I limit the amount of processed foods I eat, but don't have a seriously restrictive diet. Whole foods, and eat when I’m hungry — that's how I do it...plus the odd homemade pizza once or three times a week. 

Paul Trebilcock: My background is in ultra running, which stemmed from starting a bike courier business in the '90s, which started the adrenaline addiction. I competed in many ultras in the early 2000s. I have renewed my love of biking in the last few years as well. Training consists of anywhere from 12-20 hours a week. I mix it with running, biking, swimming, paddling, rowing and climbing. Weekends are usually longer workouts; weekdays always usually include a morning, lunch and evening workout. My diet is vegetarian steering away from gluten and sugar. I tend to stay close to a HFLC — high-fat, low-carb — diet. Most of my protein comes from dairy.  

Do you choose the races to take on? What were the toughest ones so far and why?

Donato: After bouncing a bunch of events off Paul to make sure he’s on board, I typically set the race schedule with our series producer Steven Bray. The Adventure Race Costa Rica was brutal this year. It was long, boring and just a mind-numbing slog. Egypt in season one was by far the toughest due to the extreme heat. I was running in snow the week before I headed over there!

Trebilcock: We work together on finding races. I give Simon my wish list and he and our producer put together a master list and we shorten it from there. The toughest races I experienced during season one were M2O in Hawaii and the Fish River canoe marathon, both paddling, which was out of my wheelhouse. All of our races are extremely tough, but for season two we entered the Adventure Racing World Championships, which proved to be my toughest ever. This race was a week long with about an hour of sleep a night. It traversed Costa Rica, spending hours upon hours trekking, biking and kayaking on some of the toughest terrain imaginable.  

Simon Donato during a race on the TV show 'Boundless'What were the most challenging conditions — terrain, weather etc. — that you faced?

Donato: The surprise cold snap in Iceland was brutal, but for me, it was the heat of Egypt and Cambodia in season one. The searing heat of Egypt was unlike anything I'd ever experienced, and in Cambodia, it was the humidity. It made it difficult to sleep, which made racing harder. 

Trebilcock: Paddling across the Channel of Bones in Hawaii on 15- to 20-foot swells. Climbing Munro [mountain] after Munro in hurricane winds in Scotland. Running day after day in stage races in the scorching heat of the Sahara or the wicked humidity of Cambodia. In these races we find ourselves fighting Mother Nature and ourselves constantly.  

Do you have a new appreciation for Mother Nature as a result of doing this?

Donato: I've always loved Mother Nature, which is why I do this. I love being outdoors. It's also why I became a geologist. "Boundless" has allowed me to see more of Mother Nature, which I'm very grateful for.

Trebilcock: I have always had an appreciation for Mother Nature, but doing these races in some of the most beautiful areas has definitely given me a deeper appreciation of her power and diversity.  

Have there been injuries? What has been the physical impact, and how do you deal with it?

Trebilcock: I have been fortunate not to have injuries. It totally has an impact on the body. We are shooting seasons in just over six months each. As you can imagine, these races are scheduled pretty close together; some a few days after one another. These are big endurance races, which most people do one or two of a year. We did eight in season one and nine in season two. Recovery for these races can take a while, which we don't have, so by the end of the season, the body is pretty beat up. The body is an amazing thing in its ability to adapt and it eventually gets used to and adapts to the abuse.  

Donato: I have knee trouble — patellar tendonitis — that flares up occasionally. I try to manage it during the season but with the volume that we do, it's tough to avoid at times. I'm currently trying to improve my core strength and flexibility to let my legs be as strong as they can be.

Did you ever think of quitting? What keeps you going?

Donato: It's healthy to be able to have a discussion about quitting with yourself while racing, and yes, I think about it often, especially when I'm suffering. I keep going because I know how much I hate the feeling that lingers after you quit...it's the worst! I'd rather push through the low points just to avoid dealing with being a quitter. I know I'm capable of doing anything I put my mind to. 

Trebilcock: I constantly think of quitting. When you do these races, you go through constant ups and downs. During these downs, the first thing that pops into your head is to quit. You just have to carry on knowing you will eventually hit a high and things will get better.  

Do you have jobs and families that you leave to do this? How difficult is that?

Donato: I don't have a family, but I run a gluten-free oatmeal company called Stoked Oats, as well as my expedition company Adventure Science. Add training and the "Boundless" prep, I find myself pretty busy most days. 

Trebilcock: I have a wife, two teenage girls and a job. My job is great, I work at a university as a carpenter, and they are great helping me to work the show around my job. These two seasons have definitely been tough on the family. It's the being away as well as all the training when I am back. We are all getting better at it. Just like the body's ability to adapt, we have all worked as a team to get through the tough times. I know we all love the show, which helps knowing it's working for a cool end result.  

Trebilcock and Danato hiking during the TV series 'Boundless'

Is it mind over matter when you're pushing yourself like this? What drives you to challenge yourself this way? And what do you get out of it?

Trebilcock: As a good friend of mine always says, "It's 90 percent mental and the other 10 percent is in your head." When you push the body and mind hard in a race and see what it can do, it leaves you with a taste for more. The other factor that leaves you wanting more is the "what if" factor: "What if I did this differently, how much better would I have done?" Social media has been a great motivator for me. I constantly get messages of how I inspire people. If I can motivate through these shows, that motivates me. I want to see more people get out from behind their televisions and computers and get outside.

Donato: The mind speaks; the body listens. That's how it works — the body can usually do what it’s told to do, the brain just needs to step up and give some orders when the going gets tough. You have to have a strong mind to compete in these events, especially at a high level, when the suffer-factor is greater. I've learned to thrive on the mental struggles that I endure in these events. It makes for a richer experience. I find races that don’t challenge me this way bland and boring. I always learn something about myself, and recalibrate my perceived limits. 

How old are you now, and for how long do you foresee doing these extreme challenges and the show?

Trebilcock: I am 48 years old. I am hoping we can do a few more seasons of the show. We have a great crew, and it's a lot of fun most of the time. I will go back and revisit some of the races I struggled with hopefully with a bit more training. One thing for sure is I will always be active.

Donato: I'm 37 and I foresee myself active forever, and competing as long as it continues to be enjoyable. Extreme is the only way to be for me!

What's the takeaway for the viewing audience?

Trebilcock: Hopefully, the audience takes away the fact that these races are within their grasp. You just have to get out there and get the body moving and motivated. For those already doing it, I hope it shows them some other options out there and motivates them to push a little harder.

Donato: "Boundless" shows that we are all capable of exceeding our perceived limits when we live with passion. Paul and I are regular guys, with real jobs and busy lives, yet we have the passion to push ourselves to be the best we can be on every given day.

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Follow a pair of adventure junkies as they compete in races around the world
Simon Donato and Paul 'Turbo' Trebilcock reveal what it takes to reach the finish line in the TV series 'Boundless.'