On a whim, one morning in March 2021 I remembered Wim Hof, a freaky Dutch guy known for his breathwork and cold-exposure practices, his claims that he can control his own immune system, and stunts such as summiting Mt. Kilimanjaro barefoot and in shorts, and training a group of volunteers to fight off an e. coli injection using their breath. I had been experimenting using controlled breathing and cold water to calm my mast-cell activation, and all of a sudden, I remembered this guy! I think I had read about him years ago in Outside Magazine, but I cannot tell you why I suddenly remembered his name. It was just another role my intuition played in this whole process.

I began his breathwork practice that very morning and felt instantaneous relief, primarily from the brain fog. Thus began my daily (sometimes many times a day) practice of hyperventilating until I nearly pass out, then exhaling and holding my breath out as long as I can (my record is 3.5 minutes, thank you very much.) Then I hop in some ice water.

My brain fog hasn’t returned since I began. On days when my air hunger is particularly strong, Wim Hof breathing provides some relief. And the effects are clear in my nervous system response as well: over the first two weeks of practicing, my heart rate variability doubled. I began to notice a sensation I describe as my nervous system “clearing stress.” I think I’m literally feeling my CNS switching from sympathetic to parasympathetic activation.

Sound insane? You’ve got to look this guy up, that’s all I can say.

My initial foray into breathwork led me to the incredible book “Breath,” by James Nestor. I learned more about the history of the Wim Hof breathing method (known throughout the ages by various names) as well as the physiological underpinnings of a host of other breathing techniques, many of which center around improving carbon dioxide (CO2) tolerance. I learned that the burning need to breath when we hold our breath is caused not by a lack of oxygen, but by a buildup of CO2. (Did you know CO2 actually cues the hemoglobin in blood as to where it should deliver oxygen? This is called the Bohr Effect.)

Most importantly, I learned the vital necessity of nose-breathing. Seriously. Your mouth is not for breathing, so if you are not talking or eating, shut it. I immediately began exercises to expand my palate (leaving more space for my nasal cavity) and taping my mouth shut at night. I have shifted from a part-time nose breather to a full-time nose breather, even during exercise. (There is research indicating that it is most efficient for athletes to nose breathe when training below lactate threshold, and once above lactate threshold, athletes should inhale through the nose and exhale through the mouth.) I even yawn through my nose.