by Naomi Wolfman, GNC(C), NCA, BScN
Source: Health Action Magazine, Winter 2014
Breathing is the most important function of our existence. Have you ever wondered what trajectory our breathing takes or what highlights are there along the way? Have you ever wondered how the very air we breathe affects our body?
The O2 journey
When we breathe we take in oxygen (O2), which goes to our lungs and increases oxygenation in our blood. Blood flows in one direction, just like a mountain spring, through valves that open one way only. From the lungs and through the pulmonary veins, oxygenated blood goes into the left side of the heart, filling up the left atrium, which contracts and pulses our blood through the mitral valve to the left ventricle.
As the left ventricle fills up, it also contracts and pumps the oxygenated blood through the aortic valve into—you guessed it—the aorta. From here the aorta carries the blood toward our organs and tissues to be nourished. The aortic valve works hard and can fatigue in a lifetime; this is one of the reasons aortic-valve replacements give a new meaning to life.
At its destination, the blood deposits nourishment and takes away waste, bringing it together with the poorly oxygenated blood to the right side of the heart, through the vena cava and into the right atrium. Soon this chamber fills up, contracts and the blood continues its trajectory through the tricuspid valve to the right ventricle.
The right ventricle shunts the poorly oxygenated blood through the pulmonary valve to the pulmonary artery. The blood then continues to the lungs to replenish oxygen, while the CO2 leaves our bodies through the out-breath.
What do we do next? Take another breath. And the rhythmic cycle starts once again.
The heart of the matter
None of this would be possible without the tireless, constant and reliable pumping of the heart. The heart is governed by electrical impulses that start at the sinoatrial node (SA node), located in the right atrium. The natural breathing pattern and heart rate go hand in hand. Our heart rate increases when we breathe in and decreases when we breathe out.
Numerous studies on meditation techniques recognize that breathing out (following breathing in) relaxes and calms anxieties as well as decreases or alleviates pain. This is when the “rest and digest” mode takes place, as the parasympathetic branch of the involuntary system is activated. As people, we are basically bipedal synergistic connections between the brain, body, breathing and circulatory system. This is a loving team at work: tireless, predictable, accurate and decisive.
What cues the heart rate?
Cueing the heart rate is one of the numerous functions our brain is responsible for performing nonstop, day and night. The centres that control our heart rate are located in the medulla oblongata, the lower part of the brain stem. One of these centres, namely nucleus ambiguus, increases the effect of the parasympathetic branch of the autonomic nervous system via the vagus nerve. According to the Institute for Applied Meditation, when we breathe in, the nucleus ambiguus receives inhibitory signals, the vagus nerve remains unstimulated and our heart rate increases. Conversely, breathing out activates the nucleus ambiguus, stimulates the vagus nerve and decreases the heart rate.
This teeter-totter action also affects the electrical impulses to the SA node, which fires, setting the rhythm of our pulse. As the School of Medicine Cardiothoracic Surgery faculty at the University of Southern Califiornia reports, the SA node “is the natural pacemaker of the heart.”
The right and left vagus nerves are the longest nerves in our bodies, spanning from the brain stem to the abdominal cavity and affecting our lungs, esophagus and viscera. Emotions we experience on a daily basis leave the landmarks encountered by the vagus nerve responsive, active and reactive.
Having optimal brain function gives you the comfort of welcoming life’s ups and downs calmly and collected so you can make a safe, anxiety-free decision or response.
Which leads back to breathing. Whether we suffer with colon symptoms such as irritable bowel syndrome (IBS) or constipation or with fear of the unknown or panic attacks, conscious breathing can be employed as a catalyst to help resolve and alleviate these challenges. Breathing consciously is to breathe diaphragmatically.
In breathing diaphragmatically, also named respiratory sinus arrhythmia (RSA), we take about six breaths per minute. That is about 10 seconds per breath, divided into in-breath, out-breath and allocating for the short pauses in between breaths.
By conscious breathing, I mean taking in a full breath and visualizing the bottom, middle and top of your lungs fill with fresh, clean, oxygenated air. The middle diaphragm rounds and elongates towards the bottom and pushes onto the viscera, gently massaging the internal organs and, therefore, becoming a useful and welcome motion for regularity.
Further, the abdominal cavity pushes onto the pelvic floor, which needs to stay strong enough to receive this downward pressure. Just think when you have to sneeze or cough, sing or laugh. Especially when standing up with nothing to help support the pelvic floor, gravity taking over, that tremendous pressure can add bulge to, press and weaken the pelvic fibres. This is usually a sufficient reason for anyone wanting to increase his or her pelvic-floor strength.
On the out-breath you can visualize the air leaving the top, then the middle and then the bottom of the lungs and the reverse action happens: the diaphragm pushes out the rest of the air from the deepest pockets of your lungs, slowly, as in a sigh of relief. This action creates more room within your pelvic floor. If you are inclined to use the Kegel exercise for strengthening pelvic-floor muscles, you can commence the contraction on the out-breath.
As you can see, there is much more to breathing than meets the eye.Naomi Wolfman, GNC(C), NCA, BScN, is a registered nurse specializing in continence. www.embrace-cs.ca | (604) 327-7056
(Taken from HANS