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Why I Named my Business Critical Oxygen - The Origin Story | #35 ft. Dr. Robert Jacobs


This episode of the Critical Oxygen podcast explores the concepts of critical power and critical oxygenation. Dr. Robert Jacobs and I discuss the definition and measurement of critical power, including the limitations and variability of the measurement. We also introduce the concept of critical oxygenation and its relationship to critical power. The episode concludes with a discussion on the use of NIRS for measuring critical oxygen!


1) Critical power is a measurement that represents the maximal sustainable pace an individual can maintain for extended periods of time.

2) Critical oxygenation is a related concept that represents the maximal metabolic steady state of oxygen utilization in the muscles.

3) The measurement of critical power and critical oxygenation can be influenced by various factors, including individual variability and measurement techniques.

4) NIRS devices can be used to measure critical oxygenation, but proper placement and troubleshooting are important for accurate results.

5) Muscular limitation shift towards central limitations after training.

6) Embrace new technology with healthy skepticism.

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00:00 Introduction and Overview

05:40 Definition of Critical Power

12:22 Limitations and Variability of Critical Power

30:45 Introduction to Critical Oxygen

39:17 Measurement of Critical Oxygen

44:01 Relationship between Critical Power and Critical Oxygen

51:40 Placement and Troubleshooting of NIRS Devices

52:33 Validation of Muscular Limitation

53:28 Limiter Assessment and Oxygen Delivery

54:22 Prescribing High-Intensity Interval Training

55:21 Critical Power and Performance

55:47 Translatability of Critical Power

56:16 Elusive O'W' and O'Prime

56:47 Physiological Resilience and W' Loss

57:40 Factors Affecting W' Loss

58:10 Glycogen Availability and Potassium Disbalance

59:07 Glycogen Depletion and Potassium Gradient

01:00:05 Burning Sensation and Fatigue

01:01:01 Challenging the Lactic Acid Theory

01:02:18 Embracing New Technology and Skepticism

01:04:27 The Future of Endurance Performance Measurements

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