Our autonomic nervous system, which acts as a control system of the body, has two subsystems: the sympathetic nervous system and the parasympathetic nervous system. (Some authors also include the enteric nervous system as part of the autonomic nervous system, but others do not. For simplicity’s sake, I will omit it from this discussion.)
Although the actions and interconnections of these two subsystems are quite complex, at a basic level the sympathetic nervous system is the subsystem that produces the flight-or-flight response, and the parasympathetic nervous system is the subsystem that produces the relaxation response that brings us back to normal functioning. While the actions of both of these subsystems are useful and important, the fast pace and high stress of our culture tends to overstimulate the sympathetic nervous system compared to the parasympathetic nervous system, which takes a physical toll on our bodies over time.
Fortunately, there are several ways in which the breath can be used to activate the parasympathetic nervous system to bring about a calming effect and to counteract the negative effects that overstimulation of the sympathetic nervous system has on our bodies.
The simple act of breathing through the nostrils is one way that the breath can help trigger the parasympathetic nervous system. Breathing through the nostrils has the additional benefits of warming, filtering, and moistening air before it reaches our lungs—benefits we miss out on when we breathe through the mouth. However, the simple act of the air passing through our nasal passages is one simple way to induce the calming effects of the parasympathetic nervous system in any situation.
In addition, the exhalation portion of the breath cycle triggers this calming response. The inhalation is activating, and the exhalation is calming. Obviously each breath needs to include both of these portions, but by extending the length of time spent exhaling compared to the amount of time spent on the inhale, we can generate a net calming effect. One way to do this is to inhale to a count of four and exhale to a count of eight. Adjust the counts used for the inhale and exhale to find something that is comfortable for you and does not cause your breath to become jerky or uneven, and be aware that the counts that are comfortable for you will likely lengthen over time as you practice.
The shallow breathing we normally use actually stimulates the sympathetic nervous system instead causing us great stress. Using a deep breathing that fully expands and contracts the lungs is another way to induce the parasympathetic nervous system. I will talk more about that in my next post, but I hope this one shows you that we have a marvelous tool in our breath—something we do all the time anyway—to counteract the stresses of our days without needing any fancy equipment or classes.