On The Mountain Life , best-selling author and ultramarathoning legend Dean Karnazes comes on. Karnazes has pushed his body and mind to inconceivable limits, from running in the shoe-melting heat of Death Valley to the lung-freezing cold of the South Pole. He’s raced and competed across the globe and even ran 50 marathons, in 50 states, in 50 consecutive days. In his new book, A Runner’s High: My Life in Motion , Karnazes chronicles his adventures leading up to racing in the Western States 100