If you’ve ever heard of barefoot running or considered buying an energy bar with chia seeds, you can thank Christopher McDougall’s book Born to Run, which Spandorfer calls “the preeminent running book of all time.” Driven to find out the cause of his frequent running injuries, the author tracks down members of the Tarahumara tribe in Mexico’s Copper Canyons. The Tarahumara regularly run hundreds of miles barefoot or in thin sandals (not ultracushioned running shoes) and are fueled by seeds of the indigenous chia plant instead of sugary sports drinks or protein bars. According to Miller, the resulting book “almost seems like a gonzo-style fictional story filled with characters and situations too ludicrous to be true, but entertaining and inspiring enough that it doesn’t matter.”

Spandorfer explains that it “created the barefoot running movement [and] it even sparked nutrition companies.” He notes that Health Warrior, a brand of chia-based bars and protein powders for athletes, drew inspiration for its products from Born to Run, and that minimal shoes like Nike Free sneakers took off in popularity after the book’s publication. For many runners, though, the appeal is the book’s portrayal of the love of running for its own sake. As Roll says “it helped inspire my imagination about what running could be outside of just signing up for a marathon.”