So why do we breathe? Because we want to make sure we have good energy production. There are really two real methods of producing energy, one is called the anaerobic respiration, the other one is called the aerobic respiration. Anaerobic, as the word applies, does not require any oxygen. So when you're holding your breath and you are exercising, [COUGH] you will do anaerobic respiration. So in order for the oxygen to be replenished in your body, you need to have good breathing. So why is the oxygen required? Because it is required by the mitochondrion. The mitochondrion really has two reactions that it does. One that you've probably heard of, called the Krebs cycle, and the other one, that is called the electron transport system or chain. So the Krebs cycle will output certain variants of acids and electrons, and basically, very simply put, they will be transported to the electron transport chain. And the electron transport chain will try to stabilize the high energy that the Krebs cycle has done, and separate those high energy electrons and reduce the electrons' energies to form ATP. So the energy of a free electron will be transported or transferred over to an enzyme that is going to put together phosphates to make a long chain of phosphates called adenosine triphosphate. So without the ETS system, you don't make a lot of energy. In order to make that energy production to be most efficient, it requires the use of oxygen. So this is the reason why the mitochondrial step is what's called the oxidative state. So when you're doing yoga, hopefully you're breathing in because of your posture is optimized for to fill your entire lung. So when you're taking a deep breath and you are filling the entire lung, that's when the whole lung is full of oxygen. Most of the time, you're not really breathing that hard. So there's varying levels of breathing. The normal amount of volume that you bring in and out is called the tidal volume. So when you're just sitting around and just breathing in and breathing out, in most males on average you will be breathing in about 500 millimeters. So if I tell you to stop breathing right now and take a deep breath, [SOUND], you have just sucked in what's called the inspiratory reserve volume. So that is the extra volume of air that your lung could actually inhale beyond the normal breathing rate. So if I tell you to relax again and go back to your tidal volume, and I tell you stop and breath out as much as you can, this is the volume that you'll be expelling. It's called the expiratory reserve volume. And what expiratory reserve volume is really defined as is it is the amount of air that you can expel or push out of your lungs beyond your normal breathing. So if you take a deep breath and exhale as much as you can, this is what we call the vital capacity. So that is entire lungs filling up and the entire lungs collapsing, or squeezing out every drop of air you can possibly push out. So this is the vital capacity. For most males, this will be about 5 liters. So those of you thinking, it’s like 2.5 large Coke bottles, that's what you’re doing. And you still have some air trapped inside your lungs. Because in order for you to breathe, it is a massive muscle underneath your ribcage called the diaphragm. So the diaphragm is the one that is making you actually breathe. So the lung does not expand or contract on its own, it is the muscle. So this is the reason why you need good cardiovascular health as well, as we'll talk about later on. But when you're doing yoga, you are maximizing most of this breathing. And anytime you're doing even the downward dog, what are you basically doing? You are flushing blood into your neck, and therefore they will trigger those chemoreceptors to make sure that you don't have enough acid or you do not have any acid circulating, which it will be bad for you. So what can happen to your lungs if you don't take care of them? They can fill up of water, or what we called pneumonia. So we said our lungs, human lung is actually divided into five different sections. You have, on the right side you have the top part, the middle part, and the lower part or the apical, medial, and the diaphragmical lobes of the lungs. On the left side we only have two because we have a massive muscle on the left side called the heart. So there's an apical and a diaphragmic lung. So when you're breathing tidal volume, you are really doing just the apicals. When you're doing the full vital capacity, you are filling it all the way down to your diaphragmic. So when you are not filling the diaphragmatic lobes, sometimes, because as we said before, we're constantly transporting water and carbon dioxide. Water will fill up those areas because you're not breathing out as much as you can. So this is the reason why importance of breathing exercises or when you're doing yoga. You need to get rid of the water out of your lower lungs, if they do not, they will fill up. And of course, at 98 degrees, because that is your body temperature in Fahrenheit, and it is surrounded by blood vessels, which means it has high levels of glucose that bacteria love and fungus loves, what's going to be those areas? It will be a perfect environment for bacteria to thrive, and this is what's happening when you have pneumonia. Asthma is when you have, your airway passage is narrow by two different means. Either you produce too much mucus or you are constricting it with using some smooth muscles. And of course, smoking, the reason why it's bad is because you have particles that you're inhaling. And emphysema, of course, at the end of that particle, it will blow wide enough air sacs, and you cause the disease called emphysema.
