This interview podcast features Andrew Huberman, a Stanford neurobiology and ophthalmology professor, interviewing Dr. Andy Galpin, an expert in exercise physiology, about endurance and fat loss. The discussion begins by defining endurance in various contexts (daily energy, muscular endurance, anaerobic and aerobic capacity, and sustained exertion) and debunks common myths surrounding fat loss. Dr. Galpin explains that fat loss fundamentally involves carbon exchange—ingesting less and exhaling more carbon—and that the source of energy (carbohydrates, fats, or protein) during exercise is less crucial than the overall caloric deficit. A key takeaway is that high-intensity interval training (HIIT), even in short bursts (20-second to one-minute sprints), is highly effective for improving various forms of endurance and promoting fat loss, alongside longer duration, moderate-intensity exercise. Listeners gain practical strategies for designing personalized exercise programs to improve endurance and achieve fat loss goals.