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.

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.'

The first thing I do when I walk into a hotel is find the gym, and if they don't have a gym, I start looking for a handhold where I can do my pull-ups. Sometimes if a shower curtain rod is sturdy enough, I'll do them there.

There are so many things in life that divide us, that separate us and tear us apart, be it race, religion, creed, socioeconomic level, nationality or any variety of other factors. But running is something that we all share in common.

To an extreme athlete, there's a certain appeal to doing extreme things - seeking the most extreme physical challenges in some of the most extreme climates in the world. Testing and expanding the limits of human endurance is kind of my thing.

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.

Unlike running on a road or concrete, natural surfaces are more forgiving and offer a more varied terrain, ultimately resulting in less repetitive micro-trauma to bones and joints than running on hard pavement does.

Unlike the traditional athlete, I've got to do more than just engage in my sport to put food on the table. When I'm done running, it's straight to the office.

When I was running across the country, I was doing 40 or 50 miles a day in sleeting snow with zero visibility for five or six days in a row. Ten to 12 hours of running in that is monotony beyond belief.

Yes, my dad's a marathoner. He used to do sprint distances and then started marathoning. My mom is an endurance animal. She does three-day events like the Susan G. Komen three-day walk.

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

Any goal worth achieving involves an element of risk.

I do a lot of marathons as training runs. If I'm somewhere and there's a marathon, I'll sign up and just go run it.

I have my whole office set-up at waist level; I don't sit at all during the day. Sitting, to me, is the devil.

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.

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 think I have some of my clearest thoughts when I'm out running.

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.

If you just go out there and run 100 miles, it breaks down a lot of barriers in terms of self-imposed limitations.

Personally, I don't stretch, I don't get massages. Maybe massages would be useful, but I just don't have the time for it.