Robert Mazzeo PhD is a world-renowned physiologist with a particular specialty in studying the effects of altitude on performance. His work has been influential in our understanding of how altitude affects endurance physiology and concepts such as live high, train low. Dr. Mazzeo’s free course: https://www.coursera.org/learn/science-exerciseInformation on coaching:www.trainright.comKoop’s Social MediaTwitter/Instagram- @jasonkoop