Adventure books are my personal favorites. 'The Endurance,' a story about Ernest Shackleton's legendary Antarctica expedition, or 'Into Thin Air,' Jon Krakauer's personal account of the 1996 disaster on Mt Everest, are two notables.

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.

Dean Karnazes Quotes