As Averill explains, breathing through the mouth is instinctual as it offloads more carbon dioxide than breathing through the nose. But as studies have suggested, tolerating higher levels of carbon dioxide in the body might actually signify a higher level of fitness. They have gone on to illustrate that by practising such breathing exercises, athletes actually manage to increase maximum oxygen uptake. If all that wasn’t enough to convince you, mouth breathing has been associated with por sleep and lower stamina during exercise.
So, what’s the secret behind nose breathing? The release of nitric oxide, which is shown to occur when breathing through the nose as carbon dioxide increases in the blood. Nitric oxide helps deliver more oxygen to cells which is a natural performance enhancer. According to Patrick McKeown, a clinical director at the Buteyko Clinic, “Mouth breathing is an epidemic.” In an interview with Outside, he explains: “Any athlete who trains while nasal breathing will, after several weeks, exceed their personal best, regardless of their sport.”
To practice nasal breathing, coming breath-hold exercises with such techniques like box breathing. As Averill explains, it’s an exercise that helps relieve anxiety, improves focus and builds carbon dioxide tolerance, all while seated at your desk. Simply sit upright with shoulders above hips, then breathe in through your nose for four seconds. Hold for four seconds, exhale for four seconds, and hold with your lungs empty for four seconds. Repeat this for at least five times and then work to increase the duration of each step, for up to ten seconds.