I've read that book and also Patrick McKeown's 'Oxygen Advantage', which also talks about CO2 tolerance and the benefits of Buteyko. https://www.amazon.com/Oxy

I've read that book and also Patrick McKeown's 'Oxygen Advantage', which also talks about CO2 tolerance and the benefits of Buteyko. https://www.amazon.com/Oxygen-Advantage-Scientifically-Breathing-Techniques/dp/0062349473 https://www.amazon.com/Oxygen-Advantage-Scientifically-Breat... https://www.youtube.com/watch?v=-m8jIhQyiDY https://www.youtube.com/watch?v=-m8jIhQyiDY Good stuff honestly, helped me a lot