Here is how nitric oxide works. Inside your arteries, you have what is called the endothelial layer. In The endothelial layer, there are endothelial cells that are in the artery that produce nitric oxide. Yes! The cells in your arteries already produce nitric oxide. (1)  

It is the job of nitric oxide to do a couple of things. Basically, the nitric oxide is able to penetrate through the smooth muscle tissues and thereby allow vasodilation which is the opening of the arteries and allowing more blood flow. In turn, helping the body to get more nutrients and oxygen to the cell to better help your performance and help with the overall way we feel. (2)

Nitric oxide production is ultimately created by the immune system. It is made up of macrophages. Macrophages are a specific type of white blood cell. Most people don't realize that the N02 system in our body is actually a part of our immune system. It plays a role in killing off viruses, Bacteria, and keeping the endothelial layer of the arteries healthy.(3)

The arteries are living, and they have cells that control how big and how small the arteries get, and control our oxygen delivery and our overall nutrient delivery. (4)

To help this make sense we can liken it to working out at a high altitude. Whether that workout consists of light training or hard training most of us know that it is really hard because you are not getting much oxygen. Now think about training at sea level? At sea level, it is a lot easier to train because you are getting plenty of oxygen. The same thing happens inside your body when you have enough N02 or not enough N02. Since nitric oxide increases blood flow it increases oxygen delivery but it actually increases oxygen uptake within the cell as well. (5)

This is because of something called Cytochrome C-oxidase. Cytochrome C-oxidase blocks the respiratory chain.  The respiratory chain is essentially when the body’s oxygen uptake and delivers it to a cell and the cell utilizes it. (6)

Cytochrome C-oxidase stands in front of the cell and blocks a percentage of the oxygen from being delivered. Also blocking the delivery of some nutrients. So where does nitric oxide come in? It comes in by pushing it out of the cytochrome out of the way, therefore, making it so that the respiratory chain can be completed and you can then get more oxygen to the cell which means more nutrients to the cell. Getting you a better muscle pump, better recovery after your workout, and better blood flow to the brain so you feel better as a whole. (6)(7)

There was a study done by the University of Exeter that shows the significance of nitric oxide. The study was done with beet juice which is high in nitrate which converts to nitric oxide. There were 8 test subjects and the study was performed over a span of 6 days. (8)

The test subjects were given 500 ml of beet juice. The beet juice was consumed before an intense indoor cycling workout. The same subjects were also tested with a placebo. None of the subjects were aware of the difference between the beets and the placebo (8) conclusion the study showed that when the test subjects consumed the beet juice, they found that there was a 49% increase in nitrate levels and a 19% increase in oxygen uptake to the cell. Meaning that their workouts were 19% easier. Then they also found that they lasted 16% longer in their workouts because the cells were not getting tired and they were able to get more oxygen. (8)

Nitric oxide comes in many different forms. This is a natural part of the body's production. Whether you are trying to increase your stamina, increase your blood flow, or overall performance, nitric oxide might be a good supplement for you.