WHY Elevating Carbon Dioxide with Exercise could be your Missing Link

Carbon dioxide and Exercise

Many people think: I MUST get more oxygen in during exercise in order to oxygenate my cells more effectively, but the truth is: here is yet another beautiful example of LESS is MORE.

Because of the Bohr Effect, when carbon dioxide increases in the body, oxygen LOWERS in the blood, but it RISES in the muscles and organs. I will try to avoid going ULTRA-nerd on you, but this has to do with the oxygen-hemoglobin dissociation curve. This ultimately is the representation of how saturated the hemoglobin, or the protein that carries the oxygen around, is with oxygen molecules. The higher the affinity the hemoglobin has for oxygen, the more oxygen molecules are bound to the hemoglobin and the LESS Saturated the tissues of the body are saturated with oxygen. The LOWER the affinity between hemoglobin and oxygen, the less “bound” oxygen is to the hemoglobin, and it is released to be absorbed by the tissues of the body, including organs and muscle. This is called SHIFTING the curve to the right when hemoglobin has less affinity for O2 and therefore higher absorption Into the tissues. Shifting the curve to the left is another way of saying the oxygen is clinging more tightly to the hemoglobin, and oxygen might be decreasing in tissues such as the brain and muscle.

What causes a shift to the right?

• Carbon Dioxide in blood

• pH changes in the blood to more acidic

• Higher body temperatures

What causes a shift left?

• Increased blood pH (alkaline)

• Low blood CO2 levels

Let’s dig into what actions we can take to push the curve right or left.

In order to shift the curve to the right, we have a couple of options:

Increase our body’s carbon dioxide, which can be produced through slowing our breath down, exercising, or my personal favorite: a combination of both. Many can increase CO2 levels by simply performing breath-work at very slow breathing rates along side breath retentions. The benefit of combining movement alongside slow breathing is that you do not need to be quite as aggressive with your breath-work in order to get a high carbon dioxide response because of the carbon dioxide that is produced as a byproduct of your muscles when you exercise. The coupling of both elongated exhales at a rate of around 6-10 breaths per minute with moderate intensity movement will raise the body’s CO2 levels above the normal level, something called hypercapnia. This hypercapnic state pushes the dissociation curve to the right, which increases the amount of oxygen that is being utilized by the muscles and brain. Because oxygen is the catalyst for positive change in terms of building strength and making positive brain changes from exercise, pushing your oxy-hemoglobin curve to the right during exercise could be a strategy to enhance and accelerate your results!

What does the apposite do? Pushing the dissociation curve to the left is caused by increasing the pH, or becoming more alkaline, and this can be achieved by lowering the blood’s CO2. How do we achieve this? The exact opposite of the above strategy. Breathe quickly, or hyperventilate, your way to lower blood CO2 levels. The Wim Hof Technique does this effectively. The problem with performing quick and shallow breathing in conjunction with movement is that you are increasing the affinity between hemoglobin and oxygen, and when the oxygen becomes SUPERGLUED to its carrying car (hemoglobin) it is not going to be absorbed by the surrounding working tissues during exercise. This is why many who have dysfunctional breathing during exercise, including hyper-ventilators, experience muscle cramps and/or confusion, dizziness, and anxiety. The oxygen is not getting delivered to where it needs to go when exercising the muscle!

Now we know what the dissociation curve is and why it could be a wildly beneficial strategy for you to push your curve a bit to the right when training in order to oxygenate your tissues more readily, but what other benefits are there as a byproduct of this LESS is MORE mentality in terms of oxygen? Let’s talk CO2 Tolerance!

Increasing the amount of CO2 the body can tolerate during exercise is a true sign of fitness…similar to being able to tolerate higher heart-rates, acidic conditions, lactate, and all of the elements that rise when exercise gets intense. The more we expose ourselves to these things, the more we are able to perform work while exposed to these byproducts of exercise. As a result, our body adapts the more we expose ourselves to these compounds, during which positive adaptations take place such as oxygen efficiency, lower resting heart rate, lower blood pressure, and a high state of calm.

The higher state of calm and improved cognition from performing hyper-capnic exercise is something that I want to dive into a bit more deeply because this improved ability to tolerate higher than normal carbon dioxide levels by using the tool of combined movement and breath-work is an area that I have become increasingly passionate about due to my own personal experience on top of the anecdotal accounts of hundreds of individuals going through my Hypoxix programming - a higher state of calm and increased cognitive power after combining movement with breath-work. The cognitive piece can be supported by not only the increased oxygen delivery to the brain due to the SHIFT to the right, which we now know well, but also the increased blood flow to the brain. That’s right! CO2 also has the power to increase the size of the blood vessels as a vasodilator, which increases blood flow. So, not only are we increasing oxygen, but we are also increasing blood-flow to the brain…feel smarter after breath work movements? Bingo! That’s why!

In a recent publishing in the the esteemed Cerebral Circulation - Cognition and Behavior (CCCB), A framework of transient hypercapnia to achieve an increased cerebral blood flow induced by nasal breathing during aerobic exercise, the authors summarize the benefits of mildly elevating the body’s carbon dioxide levels intermittently for the benefit of the brain [transient hypercapnia]. The authors highlight that CBF [cerebral blood flow] increases incrementally during aerobic exercise, but then plateaus at about 70% of the maximum heart-rate.

They make the point that increasing CBF during exercise is one of the main functions by which the brain’s health is increased through the increased blood and oxygen delivery. What if we could increase that blood flow even more? Well, it turns out we can, and you can achieve it through either being at altitude or manipulating your breath. Both reductions in blood oxygen and increases in carbon dioxide within the body will trigger an increased perfusion of blood to the brain with associated increases in growth factors (VEGF and BDNF) and reductions in pro-inflammatory markers with increases in anti-inflammatory markers through the shear forces of increased rate of blood flow passing over the endothelial walls of the brain vessels as the blood crosses the blood brain barrier. It is the latter activity of reversing the inflammatory markers that reduces the risk of the onset of dementia. The authors of this paper highlight that hypercapnia stimulates similar factors that hypoxic training does, which has been studied for many decades to improve brain health, including prevention of age related brain decline and improvements in neuroplasticity.

This particular paper looks at nasal breathing as a potential technique to transiently increase the body’s carbon dioxide levels, but the truth is, any type of breathing can increase it…you just have to slow it down and reduce the tidal volume (amount of oxygen) moving in and out. Trust me, I have tested it with my capno-trainer [thank you Peter Litchfield!] - it simply takes a reduction of respiration rate and volume of air. The technique that I have found extremely effective for increasing carbon dioxide levels and lowering blood oxygen intermittently within a workout is a slow 8 second exhale, inclusive of a forced exhalation to low lung volume, and a short inhale through the nose. The benefit of inhaling through the nose is that you are filtering the air, protecting yourself from viruses, increasing the body’s nitric oxide levels which increases blood flow during exercise, and increasing the amount of oxygen that is being sent to the lower lobes of the lungs, helping you to be more oxygen efficient! Try my technique out HERE for free and if you like how you feel move into an exercise protocol, in which you are intermittently challenging your brain health as you work your body and core by controlling your breath at the Hypoxix Studio!

Next reason to increase carbon dioxide levels during exercise: the higher levels of efficacy in increasing the tolerance to carbon dioxide levels and the subsequent feeling of calm that ensues! Breath-holding, especially with empty lungs, can improve your carbon dioxide tolerance over time. Free-divers, who are known to be able to sustain a breath-hold for 10 minutes +, have very high carbon dioxide tolerances and some papers have even been written on free-divers having lower levels of anxiety and depression. This could be the result of reduced sensitivity of the chemoreceptors, which have a strong association with the fear network, a grouping of fear circuits in the brain including the amygdala, hippocampus, amongst other areas that tend to be hyper-sensitive in individuals who suffer anxiety/depression. When the person who is hyper-sensitive to CO2 because of overactive chemoreceptors, panic symptoms ensue [increased breath-rate, increased heart-rate, pupil dilation, sweating]. The quickened breathing rate lowers CO2 at a rapid rate due to rapid exhalation of CO2 and inhalation of a high volume of O2 from the panicked person’s hyperventilation response. This then pushes us to higher blood oxygen levels with the associated alkaline state due to oxygen HOLDING onto the hemoglobin from low CO2 levels (remember, LEFT shift of our oxygen-hemoglobin dissociation curve from earlier?).

A panicked person is relieved when they bring themselves back to a HYPOCAPNIC or low carbon dioxide state due to the hyperventilation technique, but the problem is that they have just reinforced a negative feedback loop. By NEVER exposing yourself to higher CO2 levels because the body is mistaking it for an actual threat, the body will continue to to perceive even moderate doses of CO2 levels as threatening, immediately move to hyperventilation, and become most comfortable in a low CO2 state. Why is living in a low CO2 state not optimal? When you are hypocapnic, your hemoglobin is holding onto your oxygen…holding it hostage from the muscles and brain that could really use the O2 to get stronger, smarter, and more vital! This is why a panic attack can produce muscle cramping and confusion - oxygen is being held hostage from the muscles and brain! Don’t create a vicious cycle of existing in a LOW CO2 or HYPOCAPNIC state! My suggestion? Use a combination of movement and breath-work to expose yourself to higher than normal levels of carbon dioxide during exercise in order to increase your tolerance for CO2 and increase your blood flow and oxygen delivery all around! You can also perform breath-work in isolation, but what I like about the movement breath-work combination therapy is that you achieve those carbon dioxide spikes quicker because of the combination of CO2 offload from working muscles and the slow breathing (reducing CO2 offload from respiration!!)

Please visit my section on The Breath Source app, on which you can experience hypoxic hypercapnic training for yourself. Hypercapnic pilates sessions are truly one of my favorites…visit INTENTION on my tile to experience this core and cognition wonder! Also, want to try some hypercapnic cardio? As a former Broadway performer, I couldn’t help myself but create an 8 Week progressive dance cardio series, using Breathography as a progression! Give my online platform a try at Hypoxix Studio for hundreds of hypercapnic Hypoxic exercise programs.

Here’s to a better breath, brain, and body using a combination of movement and breath-work to achieve your top self!

AJ

OPTIMIZE YOUR BREATH-WORK + EXERCISE WITH AN AB-RIBBON!