Respiration and circulation are often talked about as if they are the same thing, but they are two different systems working together. Respiration is the mechanical process of moving air in and out of the lungs. When we inhale, oxygen enters the airways and reaches the tiny air sacs in the lungs called alveoli. When we exhale, carbon dioxide, a waste gas created by metabolism, leaves the body. Breathing itself does not deliver oxygen to the tissues. It only brings the oxygen into the lungs.
Once oxygen reaches the lungs, the circulatory system takes over. Oxygen passes from the alveoli into the bloodstream, where it binds to red blood cells. From there, the heart pumps that oxygen rich blood through the arteries and into every organ, muscle, and cell. The lungs handle the exchange of gases, but the heart controls the delivery. This is why slow, deep breathing can change how we feel so quickly. It does not just move air. It influences heart rate, blood flow, and the entire nervous system that regulates circulation.
The goal of breathing exercises is not just relaxation. It is to retrain how the respiratory system works. We are strengthening the muscles that move air in and out of the lungs, especially the diaphragm, the intercostal muscles between the ribs, and the accessory muscles of the neck and chest that assist when breathing becomes labored. At the same time, we are increasing lung capacity and improving how completely we exchange gases.
Breathing has two jobs. Bring oxygen in and remove carbon dioxide. Oxygen fuels the brain and body, but carbon dioxide is just as important because it controls blood flow and the acid balance of the brain. When carbon dioxide builds up, the blood becomes more acidic and cerebral blood flow changes. This can trigger sensations of air hunger, dizziness, panic, and rising anxiety. Many people think they are anxious first and then cannot breathe. In reality, incomplete breathing and breath holding often come first, and the rising carbon dioxide creates the feeling of anxiety.
This is why shallow breathing, breath holding, or rapid chest breathing can make the mind feel trapped, foggy, or panicked. We are not getting enough fresh air into the lower lungs and we are not clearing enough carbon dioxide out. The nervous system reads this chemical imbalance as danger. Anxiety rises because the brain feels like it is being suffocated, even if we are not aware of it.
The reason we practice breathing all the time is so that deep, complete breathing becomes automatic. When a startling thought, an emotional trigger, or a stressful moment hits, the body should naturally respond with a full inhale and a slow exhale. But for most of us, the pattern has become shallow and interrupted. We breathe in small, incomplete sips, or we hold our breath without noticing. Over time this builds up carbon dioxide and starves the brain of optimal oxygen flow.
Many people are walking around in a mild state of air hunger all day long. They do not realize that a large portion of their mental tension and anxiety is coming from this constant low level suffocation. When we train the breath, we are restoring the most basic rhythm of life. We are teaching the body how to breathe fully again so the nervous system can finally relax.