I've raced on all seven continents at least twice. I've probably run thousands of races. But the single race that I'm most proud is a 10K. Yes, a 10K. I ran it with my daughter on her 10th birthday.

I eat nothing that's processed or refined - no high-fructose corn syrup, no sugar, no trans-fats. I eat a lot of fish and monounsaturated fats from olives, olive oil and nuts. A lot of organic, fresh fruits and vegetables. No bread. No gluten. No wheat. No rice.

As long as my heart's still in it, I'll keep going. If the passion's there, why stop?... There'll likely be a point of diminishing returns, a point where my strength will begin to wane. Until then, I'll just keep plodding onward, putting one foot in front of the other to the best of my ability. Smiling the entire time.

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.

There is magic in misery. Just ask any runner.

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 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.