Dean Karnazes: 'When you’re struggling, that’s when you feel most alive'

In his latest book, the ultramarathoner takes on the ancient Greek 153-mile Spartathlon. He talks about the magic in misery and why he has stopped stoking up on pizza

Hi Dean. You have a new book out, The Road to Sparta. What is it about? It is the story and the lore of the marathon, from its genesis in ancient Greece 2,500 years ago to the modern marathon. It’s how the marathon became the marathon.

And in the book you take on the Spartathlon race [a 153-mile race from Athens to Sparta] in Gree...