CO2 Tolerance Training
Episodes covering co2 tolerance training — protocols, research, and expert discussions.
Breathing exercises to increase carbon dioxide tolerance, reducing anxiety, improving oxygen delivery, and enhancing breath-hold capacity
CO2 tolerance training is one of the most accessible interventions for reducing baseline anxiety and improving breathing efficiency. The mechanism is real: by training your chemoreceptors to tolerate higher CO2 levels, you reduce the urge to breathe, lower resting breath rate, and actually improve oxygen delivery to tissues via the Bohr effect.
Free to start, measurable with the BOLT test, and benefits multiple domains (stress, sleep, athletic performance). The science is solid and the practice is ancient.
Science & Mechanisms
Mechanisms:
- Chemoreceptors in brainstem detect CO2 levels in blood
- Repeated CO2 exposure resets sensitivity threshold
- Higher CO2 tolerance = slower baseline breath rate
- Bohr effect: Higher CO2 causes hemoglobin to release more oxygen to tissues
- Reduced breathing rate activates parasympathetic nervous system
- Nasal breathing increases nitric oxide production (vasodilator)
Key studies:
- Russo et al. (2017): Slow breathing at 6 breaths/min increased HRV and reduced stress markers
- Perciavalle et al. (2017): Diaphragmatic breathing reduced cortisol and improved attention
- Zaccaro et al. (2018): Systematic review confirming slow breathing benefits for autonomic function
Effect sizes:
- Anxiety reduction: Moderate to large effect
- HRV improvement: Moderate effect
- Breath-hold time: Large improvements with training
- Sleep quality: Small to moderate effect
Limitations:
- Most studies use general "slow breathing" not specific CO2 protocols
- Individual variation in starting CO2 tolerance
- Optimal protocols still being refined
Episodes
James Nestor, author of the bestseller "Breath," shares breathing protocols for fixing sleep and boosting performance. Covers Tummo breathing, the Wim Hof method (with warnings)...
Slow, controlled breathing directly reduces anxiety by activating specific neural pathways - this isn't placebo, it's brain circuitry. Box breathing and diaphragmatic techniques...
Mouth breathing causes structural and health problems; nasal breathing filters air and produces nitric oxide. Slow breathing at 5-6 breaths per minute optimizes CO2 tolerance. M...
The physiological sigh (double inhale, long exhale) is the fastest way to calm down. Nasal breathing should be your default, and building CO2 tolerance reduces baseline anxiety....
Carbon dioxide, CO2, is often referred to as a waste product of cellular metabolism, as well as an environmental problem as it relates to shifting the temperature of the earth w...
Aaron Alexander of the Align Podcast interviews Patrick McKeown, author of The Oxygen Advantage, in a wide-ranging conversation that begins with a philosophical discussion about...
Dr. Stephen Park, an ENT physician specializing in obstructive sleep apnea, interviews Patrick McKeown, an internationally renowned Buteyko expert and author. The episode focuse...
Andrew Huberman explains the neuroscience and physiology of muscle growth, strength development, and recovery. He covers the three-tier motor control system (upper motor neurons...
Lucas Rockwood of the Yoga Talk Show (Age Less / Live More) interviews Sasha Yakovleva, executive director of the Breathing Center and a Buteyko breathing normalization expert. ...
Dr. Andy Galpin explains how to increase control over your nervous system for long-term physiological resilience and adaptability, going beyond basic stress management to explor...
Host Ed Jones of The Holistic Navigator introduces Buteyko breathing to listeners, sharing his personal journey with the technique over several years of working with a Buteyko p...
Host Raphael of the Meditation with Raphael podcast discusses the Buteyko breathing method as a practical technique for managing anxiety. He learned about the method from a book...
Host Dana Kay of the Soaring Child podcast welcomes back Dr. Miles Nichols, a functional medicine expert and founder of the Medicine with Heart Clinic, to discuss how Buteyko br...
Dr. G delivers a comprehensive, research-backed breakdown of mouth taping, covering the physiology of nasal versus mouth breathing and why the simple act of taping your lips shu...
Host Shannon Crow of the Connected Yoga Teacher podcast interviews Steve Donald, a Buteyko educator who took the first Buteyko educator training in Canada in 2006. Steve was dra...
Brian Johnson presents a Philosopher's Notes TV book review of Patrick McKeown's The Oxygen Advantage, distilling the book into five key ideas. Brian shares that this book, alon...
Hosts Ariana Rabinovich and Catherine Cowie of the Yoga Research and Beyond podcast take a science-first look at the Buteyko breathing technique, reviewing a 2005 study publishe...
Brian Johnson of the Optimize podcast interviews Patrick McKeown, author of The Oxygen Advantage, in what Brian calls the most life-changing practice he has adopted. Brian share...