top of page
Dr Nick Tiller is an exercise scientist and researcher at Harbor-UCLA, a columnist/writer, and award-winning author.

Dr Nicholas B. Tiller is a senior researcher in the Institute of Exercise Physiology and Respiratory Medicine (Lundquist Institute) at Harbor-UCLA Medical Center. Tiller has a broad research profile, contributing numerous peer-reviewed studies in cardiopulmonary function (specifically in chronic respiratory disease), respiratory mechanics, and exercise limitation. Tiller is a leading authority in the physiology and pathophysiology of extreme exercise, a subject of personal interest in his capacity as an ultramarathon runner. He is an associate editor of the International Journal of Sports Nutrition and Exercise Metabolism.


For over a decade, Tiller has been scrutinizing the global health and wellness industry through the critical lens of scientific skepticism. His first book, The Skeptic's Guide to Sports Science: Confronting Myths of the Health and Fitness Industry, was published in 2020 and was named one of Book Authority's "Best Sports Science Books of All Time". Tiller has contributed articles on skepticism and critical thinking to numerous mainstream outlets and writes a monthly column for Skeptical Inquirer: the magazine for science and reason, published by the Center for Inquiry. Visit the 'CRITICAL THINKING' page for a collection of Nick's talks, articles, podcasts, and TV and radio spots.


Tiller is also a renowned authority on the physiology and pathophysiology of ultra-endurance exercise, particularly ultramarathon. Nick ran his first marathon in 2001 and contested Ironman triathlon (Frankfurt; European Championships) in 2009. In 2010, he ran his first ultramarathon. Since then, Nick has contested some of the world's toughest endurance races including the Marathon Des Sables (Sahara Desert) and several 100-mile trail races. In recent years, Nick has unified his personal passion for 'ultra' with his professional work in physiology, contributing original research and review papers on the subject to premier exercise science journals. In addition to peer-reviewed research, Tiller contributes articles to mainstream outlets and writes a monthly column for Ultra-Running Magazine. Visit the 'ULTRAMARATHON' page for a collection of articles, videos, podcasts, and key races.

bottom of page