We spend 1/3 of our life sleeping. And sleep is arguably one of the most important aspects of good health. Therefore, I expected that during sleep, breathing would be slow, deep, and rhythmic (i.e., “perfect”).
However, a review published in 1984 in Clinical Science showed that breathing rate is actually highly variable during sleep. In fact, breathing rates often increase and become irregular and shallow, especially during rapid eye movement (REM) sleep.
Although breathing rate might increase, the overall breathing volume is reduced, dropping as much as 16% from waking values.
This drop in volume is accompanied by relative hypoxia (low O2) and hypercapnia (high CO2). We discuss improving CO2 tolerance quite often. During sleep, your CO2 tolerance increases by as much as 66%.
What do these findings mean from a practical perspective?
Well, sleep is clearly a time when breathing should reduce and CO2 should increase. Therefore, if you are sleeping with your mouth open, you are likely overbreathing and not reaching the physiological states your body was meant to reach during sleep.
Luckily, this is an easy fix. Simply taping your mouth at night will restore nasal breathing and will provide the first step in reducing breathing volumes to their natural levels during sleep.
If you are not already, give it a shot. This one small change has had the greatest positive impact on my health and energy. It might do the same for you.
In good breath,
Nick