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Autonomic Balance for Healthy Digestive Balance

Our breathing rates play a critical role in the response of our Autonomic Nervous System (ANS). The length, depth and pace of our inhale and exhale dictate whether to activate the sympathetic or parasympathetic branch of the ANS.  

The ANS controls blood pressure, body temperature, digestion, metabolism and more. Within the ANS, the sympathetic and parasympathetic branches offer completely different physiologic and biochemical processes within these organs and systems. So, you can imagine how important balance in our ANS is for our overall health and wellbeing.

Learning Objectives:

  1. Understand the roles of the sympathetic and parasympathetic branches of the Autonomic Nervous System (ANS).
  2. Explore the relationship between the ANS and our digestive system.
  3. Learn how to bring breath into exercise to balance ANS and improve digestive function.

digestionThe Autonomic Nervous System regulates the function of our internal organs including the heart, stomach and intestines. There are two major components of the autonomic nervous system, the sympathetic and the parasympathetic systems. The sympathetic system is our fight or flight response and the parasympathetic system is our rest and restore response. Both are equally important yet have different physiologic and biochemical functions (Low, n.d.).

The parasympathetic nervous system is the branch that assists with normal, autonomic functions. In other words, we are designed to operate in parasympathetic nervous system control for most of our existence. The sympathetic nervous system is designed to prepare our body for an emergency and it always functions when our conscious or even unconscious mind notices a need for defense or to provide energy. The sympathetic system makes extra energy available and consumes it. Today, the majority of our culture is living in the sympathetic branch vs. the parasympathetic branch; which is leading to a host of chronic illness conditions we now see with heart disease, cancer, strokes, diabetes, autoimmune disease and more.

When the sympathetic system is activated, other systems and organs in the body compensate for this need for extra strength, speed or energy. Our Digestive system is one of the key systems compromised by overuse of our sympathetic branch (fight or flight) of the ANS. Digestion and urination processes are slowed to compensate for the perceived emergency (J. Physiol Pharmacol, 2011).

Our digestive function is responsible for the removal of wastes and excessive inflammation, as well as the absorption of nutrients. It also plays a role in determining our energy source i.e., burning fats or sugars to account for the energy demand. If the digestive process is routinely inhibited, we limit its ability to absorb the nutrients from the food we’re eating AND eliminate the waste, toxins and inflammation.

How Breath Influences the ANS

Mouth breathing, and/or shallow breathing, signals the brain to activate the sympathetic response as the fight or flight nerve endings are housed in the upper portion of our lungs. As we mouth breathe in exercise, we’re asking the body to produce more energy in an already stressed state. We elevate heart rates, release even more cortisol and create an acidic inflammatory response in the body. We burn and crave sugar as a source of energy.

Nasal diaphragmatic breathing signals the brain to activate the parasympathetic response as the rest and restore nerve endings are housed in the lower lobes of the lungs. Nostril breathing signals the brain that the body is safe. While exercising, we burn fat stores instead of energy reserves. Digestive function maintains balance with lower heart rates and oxygen rich blood is directed towards the musculoskeletal system instead of away from it. Exercise with more serotonin in the bloodstream is a big advantage over time in stalling the aging process and keeping digestive health strong (Cuda, 2010).

When we diaphragmatically breathe, the movement of the abdominal diaphragm is critical to the burning of inflammation, mucus and phlegm. The downward motion of the diaphragm on the nasal inhale massages the liver, gall bladder, and ascending colon on the right side of the belly. On the inhale, the massage is on the stomach, spleen and descending colon.

The downward movement of the diaphragm also activates the enteric nervous system where 95% of serotonin hormone is created along with 50% of the brain’s dopamine. The diaphragm muscle is also essential for vagus nerve stimulation. This nerve travels from the brain downward through the diaphragm into each of the digestive organs and plays a vital role in the digestive process (Vagus Nerve, n.d.).

Remember the brain is watching the length, depth and pace of each inhale and exhale and acting accordingly in every system of the body. Removing and limiting stressors from the cells is key to long-term success.

Combining the yoga breathing techniques of diaphragmatic breathing with the “ocean sounding” breath while exercising is an excellent tool for reducing a sympathetic response and encouraging balance in the ANS. Once clients master this breathing, I encourage them to lengthen their exhale twice as long as the inhale; the longer the exhale, the more parasympathetic response - or serotonin release (Cuda, 2010).

One of the primary roles of the nasal exhale is to signal a relaxation response to the brain. Most clients are in some sort of a stressed state of awareness. When we teach our clients to exhale correctly through the nostrils, the accompanying relaxation response allows the body to release and relax and burn fat instead of sugar. The nostril exhale is key to a lower heart rate. This lower heart rate raises alkalinity and drops acidity levels from the exercise period. Over time, our clients are more relaxed and have more energy from simply exhaling through the nose. The body loves these long nasal exhales because they have a cooling effect of the body’s digestive enzymes. 

When we retend the breath consciously at the top of a diaphragmatic inhale for a short period of time, the qualities of the inhale (oxygen, carbon, nitrogen) are amplified. This raises more energy for the body naturally and improves the digestive process of Digestion, Elimination and Assimilation (DEA). The diaphragm muscle becomes stronger and communicates with the vagus nerve. The phrenic nerve, the motor nerve of the diaphragm, is amplified. When these two nerves are operating optimally, the health of our gut and immune system are elevated.

Tips for Implementing the Breath:

Watch the video below for more information on the Autonomic Nervous System:


Our digestive process plays a large role in our ability to be healthy. As personal trainers, it’s our role to incorporate healthful practices with our clients. Our job is to create and provide the platform for sustainable health.


Vagus Nerve. Retrieved August 1, 2015, from

Konturek P.C/a>., Brzozowski, T., Konturek ,S.J. (2011). Stress and the gut: pathophysiology, clinical consequences, diagnostic approach and treatment options. J Physiol Pharmacol., 62(6), 591-9. Retrieved from

Low, P. Overview of the autonomic nervous system. Retrieved from

Indian, J. (1994). Breathing through a particular nostril can alter metabolism and autonomic activities. JPhysiol Pharmacol(2), 133-7. Retrieved from

Jerath, R., Edry, J.W., Barnes, V.A., . (2006). Physiology of long pranayamic breathing: neural respiratory elements may provide a mechanism that explains how slow deep breathing shifts the autonomic nervous system.Medical Hypotheses, 67(3), 566-571. DOI:10.1016/j.mehy.2006.02.042

Johnston, K., Scherer, G. (2013, June 28). Proper digestion: Essential for personal transformation. Yoga International. Retrieved From

Cuda, G. (2010, December 6). Just breathe: Body has a built-in stress reliever. Retrieved From