A fun, funny, fist-pumping romp through the thriving new fitness culture of obstacle course racing Obstacle course racing is the fastest-growing sport in U.S. history. Every week, thousands of marathoners, CrossFitters, and casual weekend warriors shell out money to run through mud and fire, crawl under barbed wire, scramble over ten-foot walls, and dodge baton-wielding gladiators. Some even sprint through electrically charged wires only to suffer muscle-seizing shocks and faceplant in the muck. In "Off Course, Outside" journalist and endurance athlete Erin Beresini dives straight into this strange world to reveal a new subculture of military-inspired amateur competition and the industry that's rapidly growing to support it. Having reached a crossroads in her own athletic pursuits, Beresini embarked on a journey to train and compete in several obstacle races herself, culminating in the world's first marathon-length event, the grueling Spartan Ultra Beast. Along the way, she met a wild cast of characters, from frat boys to housewives, fitness buffs to financiers to fanatics, and uncovered the sport's biggest scandals, lawsuits, and rivalries. As Beresini inches ever closer to her goal -- and gets pretty buff in the process -- she also illuminates the history, psychology, science, and sociology of this new sport that's taking the endurance world by storm.