In this episode of the Critical Oxygen podcast, Gabriele Gallo, Ph.D. and I explore the concept of durability and fatigue resistance in endurance sports. We discuss the definitions of durability and recovery, the importance of measuring these factors, and the role of carbohydrate availability in maintaining performance. The conversation also explores the physiological mechanisms behind fatigue and how athletes can optimize their training and nutrition to enhance durability. The discussion covers various aspects of training, including the significance of high volume, low intensity workouts for improving durability, and the ongoing debate regarding carbohydrate consumption for performance. TAKEAWAYS - Durability is defined as the ability to maintain performance during prolonged exercise. - Recovery ability refers to maintaining performance over consecutive days of training or competition. - Standardizing testing conditions is crucial for accurate durability assessments. - Maintaining glycogen levels is vital to prevent muscle fatigue during prolonged exercise. Enjoy! Enjoying these podcasts, subscribe to get notified when new episodes are released. If you have a question or topic you want me to address, leave a comment! Follow Phil on Instagram - https://www.instagram.com/criticalo2 Follow Gabriele on Instagram - https://www.instagram.com/knowledgeiswatt OR go subscribe to his substack - https://knowledgeiswatt.substack.com/?fbclid=PAZXh0bgNhZW0CMTEAAablbGSwrFjiWnk6TMrQs5Y1qRhpmA-qiDa3v8VqW_99CS1aBs0rysr07Sg_aem_OfhqsRgkHOc4XPwpcqZNKg Interested in learning more about physiology? Check out the critical oxygen website for blogs, courses and coaching -https://www.criticaloxygen.com/ CHAPTERS 00:00 Introduction to Durability and Endurance Performance 02:58 Understanding Durability: Definitions and Importance 05:49 The Role of Recovery in Endurance Sports 09:06 Measuring Durability: Methods and Protocols 11:56 Factors Influencing Durability in Athletes 15:12 The Relationship Between Carbohydrate Availability and Performance 18:04 Fatigue Mechanisms and Muscle Glycogen 20:55 Practical Applications for Coaches and Athletes 39:42 Optimizing Fuel Sources for Endurance Performance 42:05 The Balance of Carbohydrates and Fat Oxidation 44:54 Training Strategies for Enhanced Fat Oxidation 48:41 The Role of Volume in Durability Training 51:02 Carbohydrate Intake and Performance 55:49 The Debate on Carbohydrate Thresholds 01:01:01 Recovery and Inflammation: The Role of Carbohydrates 01:05:40 Future Directions in Carbohydrate Research 01:11:13 Durability Training: High Volume vs. High Intensity 01:17:56 Conclusion and Practical Applications KEYWORDS durability, endurance performance, recovery, exercise physiology, carbohydrate availability, fatigue resistance, sports science, physiological testing, coaching, athletic performance, endurance performance, fat oxidation, carbohydrate intake, training strategies, durability, sports science, mitochondrial function, recovery, exercise physiology, nutrition

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

In this episode of the Critical Oxygen Podcast, Coach Aaron Geiser and I discuss time management for endurance athletes. We discuss the common inefficiencies athletes face, the importance of scheduling workouts, and how to set boundaries to prioritize training. We discuss how athletes can evaluate their daily priorities and communicate effectively with their coaches to optimize their training schedules. Through practical tips and personal anecdotes, we provide valuable insights for athletes looking to enhance their performance by managing their time more effectively. TAKEAWAYS - Removing as many distractions as possible is essential for achieving goals. - Setting boundaries helps prioritize important tasks. - Identify what patterns allow you to be most productive. - Flexibility in training schedules is important. Doing 45 minutes of something is better than nothing. Enjoy! Enjoying these podcasts, subscribe to get notified when new episodes are released. 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 Aaron on Instagram - https://www.instagram.com/triageiser/ Interested in learning more about physiology? Check out the critical oxygen website for blogs, courses and coaching -https://www.criticaloxygen.com/ CHAPTERS 00:00 Introduction to Time Management in Endurance Training 02:49 Identifying Inefficiencies in Training 06:04 The Importance of Scheduling Workouts 08:53 Setting Boundaries and Prioritizing Training 12:11 Evaluating Daily Priorities 14:59 Managing Time for Effective Training 17:46 Communicating with Coaches for Better Time Management 28:37 Training Duration and Athlete Goals 31:28 Individualized Training Approaches 36:22 Balancing Training and Life 39:15 Self-Coaching and Realistic Expectations 44:28 Guiding Principles in Training 50:10 Incremental Improvement and Self-Assessment KEYWORDS time management, endurance training, scheduling workouts, prioritization, coaching, efficiency, athlete performance, productivity, training tips, life balance, training duration, athlete goals, individualized training, self-coaching, guiding principles, incremental improvement, time management, recovery, performance, mental health

In this episode of the Critical Oxygen podcast, Dr. Mike T. Nelson and I discuss metabolic and physiological flexibility, and explore their significance in human performance and health. We discuss the importance of being able to switch between carbohydrate and fat metabolism, the role of exercise in enhancing metabolic flexibility, and the implications of research findings on variability in metabolism. The conversation also touches on practical applications for athletes and individuals looking to optimize their metabolic health through tailored training and nutrition strategies. In this conversation, we discusses the importance of metabolic and physiological flexibility, mitochondrial health, and the role of exercise in enhancing metabolic adaptation. We emphasize the significance the concept of physiological flexibility, which includes temperature regulation, pH balance, and oxygen/CO2 management. The discussion highlights the interconnectedness of these physiological systems and the necessity of a balanced approach to training and recovery. TAKEAWAYS - Metabolic flexibility is the ability to switch between carbohydrate and fat metabolism. - Exercise plays a crucial role in enhancing metabolic flexibility. - Insulin acts as a fuel selector switch in the body. - Physiological flexibility involves maintaining temperature, pH, and gas exchange in the face of greatly changing stress environments. Enjoy! More about Mike: Mike T. Nelson, PhD, MSME, CSCS, CISSN, is a research fanatic who specializes in metabolic flexibility, heart rate variability, and human performance. He has spent 20 years of his life learning how the human body works. He has a PhD in Exercise Physiology, and a MS in Mechanical Engineering (biomechanics). He's an Associate Professor at the Carrick Institute, university instructor at Rocky Mountain University, creator of the Flex Diet Certification & Physiologic Flexibility Cert and a Human Optimization Specialist with the Special Forces Experience. He also is the Research and Human Performance Science Advisor at Tecton -makers of a unique ketone ester, and performance analysis with Rapid Health. He has published research in both physiology and engineering peer-reviewed journals. He's even been called in to share his techniques with top military agencies. In his free time he enjoys spending time with his wife, lifting odd objects, going to metal concerts, and kiteboarding. Find out more at www.miketnelson.com Enjoying these podcasts, subscribe to get notified when new episodes are released. If you have a question or topic you want me to address, leave a comment! Follow Phil on Instagram - https://www.instagram.com/criticalo2 Interested in learning more about physiology? Check out the critical oxygen website for blogs, courses and coaching -https://www.criticaloxygen.com/ CHAPTERS 00:00 Understanding Metabolic Flexibility 10:13 The Journey into Human Optimization 19:59 Research Insights on Variability and Metabolism 29:45 Practical Applications of Metabolic Flexibility 40:14 Training for Optimal Metabolic Health 54:36 Metabolic Flexibility and Mitochondrial Health 01:01:05 The Role of Exercise in Metabolic Adaptation 01:06:42 Strength Training and Muscle Mass Preservation 01:12:46 Physiological Flexibility: Understanding the Four Pillars 01:16:36 The Interconnectedness of Physiological Systems KEYWORDS metabolic flexibility, exercise physiology, heart rate variability, human performance, endurance training, carbohydrate metabolism, fat metabolism, physiological testing, energy systems, health optimization, metabolic flexibility, mitochondrial health, exercise adaptation, strength training, physiological flexibility, muscle mass, recovery, high intensity training, CO2 tolerance, health optimization

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

In this episode of the Critical Oxygen Podcast, Aaron Geiser from EndureIQ and I discuss the technology we use for training and how it informs our workouts. We emphasize the importance of rotating shoes to stimulate different muscles and prevent overuse injuries. We also discuss the use of heart rate monitors, core body temperature monitors, and NIRS devices like Moxy Monitor to gauge effort levels and make adjustments during workouts. The goal is to optimize training and avoid overcooking the body. We cover how we use technology such as heart rate monitors, power meters, core temperature monitors, and the Moxy monitor. We also emphasize the importance of measuring and tracking data to make informed decisions about training. The conversation concludes with a reminder to use technology in a way that works for each individual and to avoid becoming overwhelmed by data. TAKEAWAYS - Rotating shoes can stimulate different muscles and prevent overuse injuries. - Heart rate monitors, power meters, core temperature sensors and NIRS devices are valuable tools for monitoring internal stress and performance. - The Moxy monitor provides insights into muscle oxygenation and can be used to dictate warm-up and exercise intensities. Enjoy! Enjoying these podcasts, subscribe to get notified when new episodes are released. 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 Aaron on Instagram - https://www.instagram.com/triageiser/ Interested in learning more about physiology? Check out the critical oxygen website for blogs, courses and coaching -https://www.criticaloxygen.com/ CHAPTERS 00:00 Introduction 04:10 Training Technology Show and Tell 14:26 The Importance of Rotating Shoes 19:03 Shoe Technology and Biomechanics 29:23 Monitoring Effort Levels with Heart Rate and Core Body Temperature 37:25 Controlling Body Temperature for Optimal Performance 38:53 Using Technology to Make Informed Training Decisions 41:19 Monitoring Internal Stress and Performance 46:28 The Benefits of the Moxy Monitor 49:46 Analyzing Form and Technique with Video Recordings 53:52 Finding a Balance with Technology in Training KEYWORDS technology, training, shoes, heart rate monitor, core body temperature, effort levels, overcooking, rotating shoes, overuse injuries, biomechanics, performance, technology, training, heart rate monitor, power meter, core temperature monitor, Moxy monitor, video recording, form analysis, NIRS

In this episode of the Critical Oxygen podcast, Benedict Meixner and I discuss, maximal glycolytic rate (VLaMax) and how its measured through a 15-second all-out sprint test. VLaMax refers to the maximal rate of glycolysis or maximal glycolytic rate, which is measured through the end product of glycolysis, lactate. The standard VLA Max protocol involves a 10-minute warm-up at 1.5 w/kg, followed by a 15-second all-out sprint on an electronically braked ergometer set to isokinetic mode. Lactate measurements are taken at rest, immediately after the sprint, and every minute for up to 8 minutes. The highest blood lactate value is used to determine VLaMax. In this conversation, Benedikt and I discuss the measurement and interpretation of VLaMax for endurance athletes. We explore different methods of measuring VLaMax, including the use of Delta lactate and phosphogen contribution time. We also discuss the relationship between VLaMax, power output, and fat-free mass. The conversation highlights the importance of standardized protocols and the challenges of comparing VLaMax values across individuals. The main takeaway is that VLaMax is a significant predictor of power output in sprinting, but further research is needed to understand its relationship to endurance exercise and substrate utilization. TAKEAWAYS - VLaMax refers to the maximal rate of glycolysis or maximal glycolytic rate, measured through blood lactate production. - The standard VLaMax protocol involves a 15-second all-out sprint on an ergometer set to isokinetic mode. -VLaMax is influenced by factors such as power output and fat-free mass. - Further research is needed to understand the relationship between VLaMax and endurance exercise, substrate utilization, and the effects of diet and training on VLaMax Enjoy! Enjoying these podcasts, subscribe to get notified when new episodes are released. If you have a question or topic you want me to address, leave a comment! Follow Phil on Instagram - https://www.instagram.com/criticalo2 Interested in learning more about physiology? Check out the critical oxygen website for blogs, courses and coaching -https://www.criticaloxygen.com/ CHAPTERS Chapters 00:00 Introduction to VLaMax and the Critical Oxygen Podcast 08:06 Understanding Lactate and its Measurement 16:23 Introduction to VLaMax and its Definition 28:16 The Standard VLaMax Protocol 40:09 Measuring Lactate at Rest and After the Sprint 43:01 Determining VLaMax 45:23 Understanding VLaMax: Measurement and Interpretation 50:41 The Importance of Standardized Protocols for VLaMax Testing 56:37 The Relationship Between VLaMax, Power Output, and Fat-Free Mass 01:05:24 Exploring the Relationship Between VLaMax and Endurance Exercise 01:16:54 The Effects of Diet and Training on VLaMax 01:21:13 Optimizing Training and Performance with VLaMax Measurements KEYWORDS VLaMax, glycolysis, lactate, sprint test, ergometer, isokinetic mode, lactate measurements, maximal lactate production rate, measurement, interpretation, endurance athletes, Delta lactate, phosphogen contribution time, power output, fat-free mass, standardized protocols, sprinting, endurance exercise, substrate utilization

In this of Fast Physiology on the Critical Oxygen Podcast, Dave Schell and I discuss the stress response of our bodies to exercise and the release of stress hormones like catecholamines. We explain that exercise is a massive stress on the body, causing physiological changes such as increased heart rate and the release of stress hormones. The release of stress hormones helps the body adapt and try to establish a steady state during exercise. TAKEAWAYS 1) Exercise is a massive stress on the body, causing physiological changes and the release of stress hormones. 2) The release of stress hormones helps the body adapt and establish a steady state during exercise. 3) Chronic stress can blunt the body's ability to adapt and negatively impact overall health. 4) Managing stress, both in training and in life, is crucial for optimal adaptation and performance. 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 and Transition to Stress Hormones 10:09 Differentiating Between Cortisol and Epinephrine KEYWORDS exercise stress response, stress hormones, catecholamines, physiological changes, managing stress

In this episode of the Critical Oxygen Podcast, Coach Aaron Geiser and I discuss the importance of individualized nutrition for endurance athletes. We emphasize the need to tailor nutrition plans to each athlete's specific needs and goals including individualized fueling in race. Aaron introduces the the right fuel at the right time motto and how EndureIQ uses it to optimize performance. The conversation highlights the significance of proper nutrition in preventing GI distress and improving race performance. We encourage athletes to try different fueling strategies during training to find what works for them. TAKEAWAYS - Nutrition needs to be individualized based on an athlete's specific needs and goals. - Low-carb diets may not be suitable for all endurance athletes, and carbohydrate intake should be tailored to the intensity and duration of the exercise. - Proper nutrition plays a crucial role in preventing GI distress and improving race performance. Finding the right carbohydrate intake is crucial for endurance athletes, but it is a highly individualized process that requires experimentation. - Carbohydrate intake on the bike and run should be adjusted based on the differences in movement and GI distress potential. CHAPTERS 00:00 Introduction 02:16 The Importance of Individualized Nutrition 05:30 Optimizing Performance with the Right Fuel at the Right Time 09:40 Dispelling Misconceptions about Low-Carb Diets and properly fueling 14:53 Preventing GI Distress and Improving Race Performance through Nutrition 30:28 Finding the Right Carbohydrate Intake 32:20 Don't Blindly Follow Studies and Marketing Claims 33:43 Experimenting with Different Nutritional Supplements 35:08 Consider Flavor and Simplicity in Nutrition Products 39:27 Stick with What Works for You 45:19 Optimal Carbohydrate Intake for Exercise Intensity 48:16 Avoid Hyper Optimization of Carbohydrate Intake 57:21 Managing Carbohydrate Intake for Longer Races KEYWORDS individualized nutrition, endurance athletes, right fuel right time, carbohydrates, GI distress, race performance, carbohydrate intake, endurance athletes, individual experimentation, absorption, GI distress, fueling

In this episode of the Critical Oxygen podcast, Dr. Andri Feldman and I discuss the importance of oxygen and how to measure oxygen dynamics in the muscle using near-infrared spectroscopy (NIRS) devices like Moxy Monitor. We explain the physiology of oxygen and its role in energy production through ATP synthesis. We also explore the different energy systems involved in exercise, including the phosphagen system, glycolytic system, and oxidative mitochondrial system. The conversation highlights the interconnectedness of these systems and the role of lactate as an intermediary. We then explore the principles of NIRS and how it measures oxygenation levels in the muscle. Overall, NIRS is a valuable tool for monitoring and optimizing training performance. TAKEAWAYS - Oxygen is crucial for energy production through ATP synthesis in the body. - The phosphagen, glycolytic, and mitochondrial oxidative phosphorylation systems are the three main energy systems involved in exercise. - Near-infrared spectroscopy (NIRS) devices like Moxy Monitor can measure oxygen dynamics in the muscle and provide insights into an athlete's performance. - Near-infrared spectroscopy (NIRS) measures oxygenation levels in muscles and can be used to determine steady state and critical power or even functional threshold power (FTP). - NIRS provides real-time feedback on oxygen supply and demand, allowing athletes to adjust their training intensity accordingly. Enjoy! Enjoying these podcasts, subscribe to get notified when new episodes are released. If you have a question or topic you want us to address, leave a comment! Follow Phil on Instagram - https://www.instagram.com/criticalo2 Interested in learning more about physiology? Check out the critical oxygen website for blogs, courses and coaching -https://www.criticaloxygen.com/ CHAPTERS 00:00 Introduction 07:10 The Importance of Oxygen and Energy Production 19:31 The Three Energy Systems in Exercise 25:20 The Role of Lactate as an Intermediary 38:26 Measuring Oxygen Dynamics with NIRS 42:19 How NIRS Works 43:41 The Importance of Oxygenation and the Role of NIRS 45:08 Understanding Muscle Oxygenation and NIRS Measurements 46:03 Using NIRS to Measure Oxygen Supply and Demand 47:23 Interpreting NIRS Readings and Muscle Oxygenation Levels 48:20 The Relationship Between NIRS and Oxygen Delivery 51:22 The Significance of Steady State in Exercise Physiology 52:49 The Importance of Maximal Sustainable Exercise Rate 56:07 The Relationship Between Oxygenation and Lactate Production 59:44 Comparing NIRS and Lactate as Performance Metrics 01:04:19 Using NIRS to Determine Training Zones and Thresholds 01:08:04 The Benefits of NIRS for Training Optimization 01:19:24 Triangulating Data Sources for Informed Training Decisions KEYWORDS oxygen, near-infrared spectroscopy, NIRS, energy systems, ATP synthesis, phosphagen system, glycolytic system, oxidative mitochondrial system, lactate, near-infrared spectroscopy, NIRS, oxygenation, energy systems, lactate production, muscle fatigue, steady state, critical power, training intensity, monitoring, optimization