Jim Gourley’s ‘Faster: Demystifying the Science of Triathlon Speed‘ shows how to shed race time by focusing on physics rather than fitness. “Free speed does exist,” writes Gourley, who is a triathlete and astronautical engineer (a.k.a. rocket scientist). “You just have to know where to find it.” His illustrated, easy-to-follow chapters break down the most efficient swimming, running, and biking form. The book also demonstrates the benefits of weight versus aerodynamics in bikes, and provides insight into the most impactful gear upgrades.