Hillary Allen is from Fort Collins, Colorado. She grew up in an outdoorsy and scientific family who not only encouraged her to pursue a career in science but also in sport. She earned a master's degree in neuroscience and physiology and structural biology from the University of Colorado. During her graduate studies, Hillary also discovered trail running and ultra-running. Her passion for the outdoors quickly led to success on the trails where she became a sponsored mountain runner for The North Face. Along with her professional running and racing career, Hillary also teaches chemistry, biology, anatomy and physiology part-time at a small college outside of Boulder, Colorado. She also coaches other runners, again using her love of athletics and her physiology background.