How to Maintain a High CO2 Tolerance

Wim Hof: I'm most focused on keeping my CO2 tolerance really, really high. And so when I go into my breath holds, I could do it much longer than if I was just to start trying to hold my breath right now. So as I increase more nitric oxide, I get, it'll help relax me a lot of parasympathetic nervous tone. Also helps with sexual performance as well. Sea allysin biagra work off of basically the same kind of neurotransmitter as nitric oxide. It's just a very powerful tool in that sense as well.