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.

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.

Want a strong, solid relationship that is willing to go the distance? Get to know your running shoes.

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.

Somewhere along the line we seem to have confused comfort with happiness.

Struggling and suffering are the essence of a life worth living. If you're not pushing yourself beyond the comfort zone, if you're not demanding more from yourself - expanding and learning as you go - you're choosing a numb existence. You're denying yourself an extraordinary trip.

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.