In this of Fast Physiology on the Critical Oxygen Podcast, Dave Schell and I discuss mitochondrial respiration and its importance for endurance training and performance. We discuss the common misconceptions surrounding fatmax and VO2max, especially as it pertains to mitochondrial respiration. We also highlight the significance of both high-intensity and low-intensity training, advocating for a balanced approach to optimize mitochondrial function and overall athletic performance. TAKEAWAYS 1) Mitochondrial respiration is maximal at VO2 max, not fat max. 2) Fat max is related to the ability to oxidize fats, but not the sole indicator of performance. 3) Zone two training enhances mitochondrial density and fat oxidation. 4) High-intensity interval training significantly increases mitochondrial function. If you have a question or topic you want us to address, leave a comment! Follow Phil on Instagram - https://www.instagram.com/criticalo2 Follow Dave on Instagram - https://www.instagram.com/kaizenendurance/ OR YouTube - https://www.youtube.com/@UCT5Cy95BiLIDQh4KS5bohhQ Interested in Gravel or Mountain Bike Coach? Head to Dave's website - https://www.kaizenendurance.coach/ Want to learn more physiology, check out my blog, and courses - https://www.criticaloxygen.com/ CHAPTERS 00:00 Introduction to Mitochondrial Respiration 01:18 Understanding Mitochondrial Stimulation 05:03 Maximal Mitochondrial Respiration vs. Fat Max 10:27 Practical Applications of Fat Max Training 15:27 The Role of High-Intensity Training 21:55 Balancing Training Intensities KEYWORDS mitochondrial respiration, fat max, VO2 max, endurance training, exercise physiology, ATP synthesis, high-intensity training, fat oxidation, performance, metabolic health