Two million years ago, Africa: A skinny, long-limbed creature who walks on two legs, can't sprint, and has no weapons turns away from his under-nourished friends, and runs down a much stronger antelope. Dinner. Over succeeding generations, this creature evolves into one of the best distance runners on the planet: the human being. Yet in the age of modernity, we find ourselves unable to run without more than half of us suffering injury. This book looks at the injury epidemic in running and what the barefoot running movement believes are the causes of injury. It analyzes the best-seller Born to Run, how human evolution has shaped our bodies, how modernity has warped those same bodies, and what barefoot running both got right and wrong. It concludes by giving practical advice to runners from the writer, a 2012 Olympic Trials qualifier in the marathon.