How high or far or fast can humans go? And what about individual potential: what defines a person's limits? From running a two-hour marathon to summiting Mount Everest, we're fascinated by the extremes of human endurance, constantly testing our limits. In Endure Alex Hutchinson, Ph.D., reveals why our individual limits may be determined as much by our head and heart, as by our muscles. Showing how anyone can utilize tactics to bolster their own performance.