Jason Robillard has been doing ultramarathons for many years, and started advocating for barefoot running before it was cool and is considered an authority on it.
In this guide, he teaches trail-running newbies and experienced marathoners essential survival skills and tips for running long distances: how to run in snow, ice, and mud; how to cross large streams of water; what to do when you have to go number 2 on mile 30 of a 50-mile run; preparing for trouble (building a fire, surviving in the heat and cold); running in thunderstorms.
The book is written with an irreverent sense of humor and touches on topics that many running books don’t get into.