In this talk, Dr Seiler explains in words and pictures how modern exercise physiology laboratories reveal the body’s remarkable capacity for adaptation. He also tells us about the “laboratories” developed by athletes and coaches since the start of the Cold War in the 1950s. The laboratory of the scientist and the laboratory of the coach/athlete come together as Dr. Seiler describes his own journeys back and forth between them. By connecting the power of both, we have learned why “no pain no gain” is a slick slogan, but a fundamentally flawed approach to getting faster and fitter over time. Stephen Seiler has spent years studying the training habits of great endurance athletes. What he discovered has shattered the myths he grew up with in the US. Let him tell you why going “green” is also important for building endurance sustainably. This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at https://www.ted.com/tedx