In this episode of Fast Physiology on the Critical Oxygen Podcast, Dave Schell and I engage in a spirited debate about the utility and accuracy of physiological assessments, particularly ramp/step tests. We discuss the importance of understanding physiological variables, the differences between lab and field tests, and the value of physiological testing in tracking performance over time. We also discuss the nuances of physiological testing and how different types of tests can effect physiological outcomes. The conversation highlights the nuances of testing methods and the need for flexibility in training approaches. TAKEAWAYS 1) Physiological assessments are crucial for understanding an athlete's underlying physiology and their endurance performance potential. 2) Ramp and step tests can provide valuable information but their design is nuanced and there are some potential limitations. 3) Field tests may offer practical alternatives to lab tests but do not directly measure physiological outcomes. We would love for you to weigh in, what's your take on the use of physiological testing for coaching endurance athletes? 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 Physiological Assessment 02:02 The Debate on Ramp Tests 08:35 Understanding Physiological Variables 15:52 Field Tests vs. Lab Tests 22:48 The Value of Physiological Testing KEYWORDS physiological assessment, ramp tests, endurance training, VO2 max, exercise physiology, field tests, lab tests, performance tracking, endurance athletes, training methods