What's keeping you from achieving your fitness goal?
Learn more about the Oxygen transport system, how you can identify any performance-limiting factors related to it, and how to fix them.
Oxygen is the molecule that keeps us alive, powers our movement, and helps us grow. That’s because it’s the key element our body uses in the process of producing the energy we need to move and power our lives. This process is called metabolism.
Although metabolism is a combination of several functions it can be summarized as the process through which our body breaks down nutrients (e.g. fats and carbohydrates) to release the energy they contain. The breakdown process of nutrients requires oxygen and therefore even the shortest disruption in oxygen supply will immediately diminish our body’s ability to produce the energy it needs to keep our heart beating, our brain functioning, or our legs moving.
Four systems are participating in the process of oxygen supply: Heart, lungs, bloodstream, and cells. First, our lungs absorb the oxygen from the air we inhale which then enters the bloodstream. Oxygen-rich blood is then pumped through our heart to our body where it’s absorbed by our cells, which use it to burn nutrients and release the energy they contain (i.e. calories). Figure 1 provides an overview of how these systems function. Achieving any fitness goal, from dropping a few pounds to completing a triathlon, depends on the effective operation of these 4 systems. Therefore, identifying the system(s) that pose a limitation in the transport of oxygen is the most vital insight you need to develop a fitness plan that will get you to your goal as fast as possible. Here are a few examples:
Improve your time in running, cycling, or swimming
Endurance sports are one of the most prominent cases where finding your oxygen transport limitation will propel your performance. Given that these activities require continuous production of energy for keeping your muscles going for prolonged periods, keeping the oxygen supply undisrupted is vital. The most frequent types of limitations we come across in PNOĒ typically affect the lungs and cells. In the case of lungs, the limitation is typically manifested in the form of over-breathing or shallow breathing. In simple words, athletes often breathe faster than they should (i.e. hyperventilate) or breathe without using their entire lung capacity. Both cases result in limiting the oxygen supply to the body, therefore the amount of energy and movement muscles can exert. On the other hand, a limitation in the cells is manifested by their inability to absorb oxygen effectively enough. That’s normally due to decreased mitochondrial density and also results in a lower ability to generate energy and move your body. What’s important to understand is that to achieve optimal performance, one needs not only to deliver oxygen to the working muscles (i.e. ensure lungs, heart, and circulation work well) but to also absorb it (i.e. ensure that cells can use it).
As we discuss in our blog “Why diets fail” a reduction in your metabolic activity caused by excessive calorie restriction or cardio training is the number one factor leading 90% of diets to fail. A reduction in metabolic activity, AKA a slow metabolism, means that your body burns fewer calories than normal due to a series of hormonal perturbations. This reduction in energy consumption or increase in movement economy is predominately due to an increase in muscular-skeletal efficiency. In simple words, your muscles become more efficient and burn fewer calories for the same amount of work . This is because your muscle cells “deactivate” processes to reduce their energy consumption, which inevitably leads to less oxygen absorption. Overall, a slowdown in your metabolism is ultimately manifested as less oxygen absorption by your cells.
Oxygen transport is the most important function in the human body. It keeps you alive, dictates your athletic performance, and regulates your weight. Understanding which system poses a limitation in the oxygen transport chain is the most important step towards identifying the most effective plan for your body. The PNOĒ breath analysis test provides an easy and highly accurate method for assessing how efficiently your body’s systems transport oxygen, identifying any limiting factors, and prescribing the plan to fix them.
Adaptive thermogenesis in humans., Int J Obes (Lond). 2010 October; 34(0 1): S47–S55. doi:10.1038/ijo.2010.184.