Dean Karnazes

I have an ElliptiGO. It's a standup bicycle. You don't pedal; you stride on it. It allows me to have the same striding motion as running without the impact.

I went to college, grad school. I got an M.B.A., had a really cush corporate job. But I was just bored stiff. I didn't fit that mold.

Any goal worth achieving involves an element of risk.

Runners are competitive folks. I think some might feel slighted they haven't got more recognition. I think they have a point. In running, you won't necessarily get noticed just for turning in good performances.

Toeing the starting line of a marathon, regardless of the language you speak, the God you worship or the color of your skin, we all stand as equal. Perhaps the world would be a better place if more people ran.

Running back-to-back races requires a certain tactical prudence. Going too hard in any one race might jeopardize your performance in another. Maintaining proper hydration and caloric equilibrium also becomes increasingly critical.

Many athletes are seeking new and novel ways of pushing their limits, and the challenge of running back-to-back races is certainly one way to test the boundaries.

Running was a part of my hardwiring, and that's what I wanted to do. So this is what I tell people who talk about wanting to follow their passion. 'It doesn't have to be running. It can be basket weaving. Be the best basket weaver in the world. Throw your heart and soul into it.'

Beyond racing, I just love the art form of running, of conceiving new ideas like the 50 Marathons in 50 States in 50 Days. It's the ultimate expression of what I love to do, which is run, and travel, and see this great country.

I love to run and I have some tips to keep it fresh and novel. I rarely use the same route twice. That keeps things new.

I love surfing, rock climbing, cycling - all that stuff. But it's just amazing that I can inspire people with my running. It's humbling, really.

A lot of ultramarathoners are soloists. They're single and live lives off the grid.