Like the beating of the heart, breathing is one of the bodily functions that doesn't require any thought input. Most often, we rely on chemical sensors in the brain to control our breathing rate and depth, and they work by measuring the oxygen and carbon dioxide levels in the bloodstream. Oxygen is needed to combine with a fuel source (such as carbohydrates or fats) in order to produce energy for the body.
Relaxed vs Forced Breathing
The diaphragm is a dome muscle that separates the abdominal and thoracic cavities (See picture below). This muscle is involved in relaxed breathing, when the abdomen is relaxed. During inspiration, the diaphragm flattens out and pushes downwards on the organs in the abdomen, resulting in the lungs being able to expand downwards and take in more air. Since the body is relaxed, this enables the organs to push out against the abdominal wall, which is also relaxed. During expiration, the diaphragm simply relaxes and the elasticity of the lungs pushes the air back out.
When the body needs an increase in respiration rate, this is usually due to some sort of physical activity. Since the abdominal muscles are contracting and providing more resistance for the abdominal organs to push outwards, the body cannot rely on the diaphragm muscle to have the same effect. It now relies on the accessory breathing muscles to help expand the chest cavity. The major accessory muscles include the scalenes, sternocleidomastoid, pectoralis minor, serratus anterior, along with the 3 layers of intercostal muscles (external, internal, innermost) that lie between each rib). All of these aid in forceful inspiration, except the internal and innermost intercostal muscles, which have a role in forceful expiration.
Are you breathing the wrong way?
Often, when someone has poor posture or increased stress, they can become "chest breathers", which means they use their accessory breathing muscles while they are relaxed. Since most of these muscles attach to either the neck or the shoulder blade, this can result in these muscles being overworked and lead to neck and shoulder problems. This also effects the efficiency of the body to intake oxygen, leading to a decrease in energy levels or even more use of these accessory muscles (which furthers the problem). One way to test this on yourself is to look at your breathing in the mirror. If you are relaxed and your shoulders and chest are rising which each breath, this is abnormal.
How can you correct this?
A good exercise to help correct "chest breathing" starts with lying on your back with a light book on your stomach. Next, place one hand on your chest, and one hand by your side so your fingers are touching your low back. Focus on breathing with the diaphragm by pushing the abdomen out against your bottom hand and the stomach. The book should raise up towards the ceiling with each breath and the hand on your chest should not move. Once this is mastered lying down, you can try it in different positions.
Illustration by Beth MacDonald.
Dr. Shawn K. Exley, A.S., B.Sc., D.C.
Dr. Shawn K. Exley is the owner of Yaletown Chiropractic in Vancouver, BC. He graduated with his Doctor of Chiropractic (DC) degree from the University of Western States in Portland, Oregon. He has always had a desire to help others and shortly after being introduced to chiropractic, he saw how beneficial it was in supporting his active lifestyle.