I’ve spent a few weeks writing about breathing – all kinds of breathing. Ever wonder what happens to all that oxygen when you breathe it into your lungs? What does that oxygen do for you? How is it converted to energy? What are the mechanics?
Your respiratory system works alongside your cardiovascular system (heart and blood vessels) to supply your organs with fuel at the cellular level, where it is bio-chemically converted to energy so your organs, muscles, brain and the rest of your body function. Here’s how it works.
Your respiratory system, consisting of your lungs and the “tubes” from your nose and mouth, collects the oxygen you breathe in and transports it into your bloodstream. It’s your heart and blood vessels that are responsible for getting the oxygen from your lungs to the cells of your body to make it work. Once that oxygen (and other nutrients) get to your cells, your blood which is now loaded with carbon dioxide and other waste products, returns to your heart and lungs where the bad air is exhaled and the cycle starts over again. When you exercise, you inhale more oxygen and the heart pumps your blood throughout your body much faster to keep your energy up and your body working. We learned in High School that Arteries carry oxygenated blood away from your heart, and veins bring the carbon dioxide filled air from the body back to the heart and lungs. Remember the diagrams? Arteries were red and veins were blue.
“In a simplistic overview, oxygen and carbon dioxide trade places in the tissues of the body, blood, and lungs. As one is coming in, the other is going out.” — NASM Essentials of Personal Fitness Training, Third Edition, p. 50.
What happens with all that oxygen when it gets to your cells? Simply speaking it provides your body with energy. Energy is “capacity to do work”. “Bioenergetics” is the study of human energy and how food and oxygen are converted into energetic capacity. The “Bioenergetic Continuum” is the pathway that energy creation takes. Just thought you’d want to know.
It seems that most cells have something in them called mitochondria. These little jewels are called the “furnace of the body” and create energy through a chemical reaction to form ATP (Adenosine triphosphate) which is the fuel source for the cell. Muscle cells have more mitrochondria per cell than others and use the most energy. The waste product from all of this is Carbon Dioxide and is sent back to the heart and lungs to be eliminated when you exhale. That’s about all there is to it. And that’s about as far as I am going to take this except to point out that the muscles burn either fat or glucose depending on the type of exercise you are doing (running vs. sprinting or lifting light weights vs. maximum capacity heavy weightlifting), and affects the way the ATP is combined with other chemicals.
I tried to keep that as simple, understandable and useful as possible. Whether I succeeded or not is up for question. I promised to write about it and I kept my promise. But if it was still too complicated, here is the way your grandkids learn it: (Source: biology4kids.com)
“Using Oxygen to Release Energy
How does cellular respiration occur in mitochondria? The matrix is filled with water and proteins (enzymes). Those proteins take organic molecules, such as pyruvate and acetyl CoA, and chemically digest them. Proteins embedded in the inner membrane and enzymes involved in the citric acid cycle ultimately release water (H2O) and carbon dioxide (CO2) molecules from the breakdown of oxygen (O2) and glucose (C6H12O6). The mitochondria are the only places in the cell where oxygen is reduced and eventually broken down into water.”
Oh, now I get it. Thank you for reading.