Why Does Deep Breathing Actually Work?

By Kristen Sohlman, HBA, RP

​How does deep breathing work?
Deep breathing communicates with the nerves responsible for the body’s emergency responses, fight or flight, to slow down and to maintain a sense of calm.  The Fight or Flight response prepares the body for an anticipated danger by propelling it into a heightened state of alertness or readiness.  This natural state keeps the body out of harm’s way when there is an actual threat, like if a wild animal escaped from the zoo and was right in front of you!  A signal is sent to the brain telling the body that there is an emergency and breathing becomes fast and rapid so that we can either run away or stay and fight.  We may also experience an increase in heart rate, blood pressure, and a shortness of breath or shallow breathing.  

The challenge is that we can feel this way even when there is no actual threat or emergency, and we may feel fearful, anxious, or angry because it is a difficult situation.  For example, someone may become anxious about public speaking when there is no actual risk of harm to themselves if they were to speak in front of a group. 

By taking slow, controlled breaths, the arousal centre of the brain is not activated and we can stay and face the situation in front of us instead of fighting or fleeing (or experiencing all of the urges to do so without actually being able to leave). 

Our bodies have two opposite systems that function much like the gas and the brakes of a vehicle.  The sympathetic nervous system (the gas), and the parasympathetic nervous system (the brakes). 

When we breathe deeply, the gas is suppressed and the brake is enhanced.  Deep breathing pushes the brakes by activating the hypothalamus, connected to the pituitary gland in the brain, to send neurohormones that inhibit stress-producing hormones and trigger a relaxation response in the body.  The hypothalamus links the nervous system to the endocrine system, which secretes hormones that regulate the body and controls how a person copes with stress.  Epinephrine or adrenaline, and norepinephrine or noradrenaline are the hormones that increase heart rate and blood pressure, preparing the body for the fight-or-flight response. 
 
How is this helpful?
When we breathe deeply, we push down the brakes. The brain sends a message to the body to decrease the stress hormones, and our heart rate and blood pressure decrease.  We then feel less stressed physically so that our minds can follow. 

Sometimes we are consciously willing to address our issues, but cannot think clearly and become overwhelmed because we are too far into that state of fight or flight. We are gearing up to run away rather than staying calm, thinking things through, and taking logical steps.

It can be difficult to breathe deeply when you are anxious or angry, but with time and practice, it gets easier and more effective. By focusing on deep breathing you are more focused on your breath and being in the present moment, and are no longer focused on what it is that is creating the stress in your life.  This can give you the needed break to seek out support or try other coping strategies that you have in your coping skills tool kit. 
 
For more information, check out The Science of Slow Deep Breathing by M. MacKinnon (Psychology Today, 2016).

References:
MacKinnon, M. (2016). The Science of Slow Deep Breathing. Psychology Today. [Web page] Retrieved from https://www.psychologytoday.com/blog/neuraptitude/201602/the-science-slow-deep-breathing