Even if dancing isn’t your thing, Imagine a dance, where two partners move in harmony with each other.
This dance, with vital life-supporting molecules of oxygen (O2) and carbon dioxide (CO2), takes place in your body every moment you breathe and live.
Just like a dance requires balance of movement and rhythm, our bodies need the right balance of O2 and CO2 to function optimally.
During my breathwork training, I became familiar with these terms and how to apply them practically.
Let’s dive into three essential aspects explaining this delicate balance in our bodies:
Bohr Effect, BOLT test, and CO2 tolerance test.
Decoding Breath Metrics: The Bohr Effect, BOLT Test, and COz Tolerance Test
The Bohr Effect: Balance in Every Breath
Discovered by Danish physiologist Christian Bohr in 1904, the Bohr Effect changed the way we understood respiration.
To explain it in simple terms: when there’s more CO2 in your blood, your red blood cells release more oxygen to surrounding tissues that need it.
This ensures that during physical activity or stress, when our tissues produce more carbon dioxide, they receive the required oxygen levels to function properly.
This Bohr Effect phenomenon is the foundation of how O2 and CO2 maintain their balance in our system.
How our body manages Respiratory System Regulation:
. When CO2 levels rise (hypercapnia), the body’s immediate response is to increase the breathing rate and depth, helping to expel excess CO2 and bring in more O2.
. On the other hand, a significant drop in O2 levels (hypoxia) also stimulates an increase in breathing rate to take in more oxygen.
Understanding Oxygen Levels first: You may be surprised, but our arterial blood is usually rich in oxygen. In a typical healthy individual, oxygen saturation is around 93-99%. The main challenge is using this oxygen effectively and maintaining a balance with other gases like CO2.
BOLT – Body Oxygen Level Test: And no, it doesn’t involve running like Usain Bolt-famous retired Jamaican sprinter.
How do we measure our body’s efficiency in managing this O2 and CO2 balance?
The BOLT test provides an answer. It is about- how long you can comfortably hold your breath after a normal exhalation.
Higher BOLT score indicates better tolerance to CO2, implying that your body can efficiently utilize oxygen-to tramsport it and use it for energy production in cells and for metabolic processes, like waste removal for example.
CO2 Tolerance Test: The CO, tolerance test provides a deeper understanding of our body’s response to CO2.
Our natural impulse is to breathe more rapidly when CO2 levels in our body rise. This test challenges that natural breathing reflex, helping us understand our tolerance and our body’s efficiency in managing CO2.
Individuals with higher CO2 tolerance often experience less anxiety and usually perform better in high-stress situations.
I highly recommend “Oxygen Advantage” by Patrick McKeown as a must-read on these topics.
Always Safety First: Before and while practicing
I always advise for moderation while practicing. Breathing techniques should be taught ethically and responsibly.
- Never push yourself to the point of feeling dizzy or gasping for air.
- Do not perform these tests while driving, swiming or under water or while walking
- Avoid doing these test if you have any serious medical conditions or are unsure about your respiratory health.
- If in doubt, consult with a doctor before trying.
Putting It into Practice: How to Conduct BOLT & CO2 Tests
BOLT TEST – how to perform:
- Relax and Breathe Normally: Sit comfortably and take a few minutes to breathe calmly and naturally. Inhale and exhale through your nose, no mouth breathing please.
Take a Normal breath(the way you usually breath): After a normal inhalation through your nose and a passive exhalation (not forced) through your nose, do not inhale, pinch your nose and hold your breath. - Time your breath- hold: Start a timer on your phone. The moment you feel the first distinct urge to breathe, the so called- breath hunger, release your nose and start breathing again. This isn’t about holding your breath as long as possible, but rather until you feel the initial need to breathe.
- Note the Time: The time from when you stopped breathing to when you felt the first urge to breathe is your BOLT score, measured in seconds.
Interpreting the BOLT Score:
- Less then 10 seconds: this indicates that your breathing pattern is irregular, you are probably mouth breathing often and it indicated very low CO2 tolerance.
- 10-20 seconds: This suggests lower breath control and a potential for over-breathing or hyperventilation. It can indicate lower CO2 tolerance.
- 20-30/40 seconds: Represents an average score for most of us and decent CO2 tolerance.
- Over 30/40 seconds: You have a very good breath control and a high tolerance to
CO2. It often signifies efficient breathing patterns better then average (average is 12-20 breaths per minute.)
BOLT Test in Yogic Pranayama:
While BOLT test itself might not be a traditional component of Pranayama, the principles of breath awareness, control, and retention are foundational in Pranayama practices.
Using the BOLT test in combination with Pranayama practices provide a measurable way to improve your progress in better breathing over time.
Remember, breathing exercises have a compound effect on our health: the more you practice, the more efficient it becomes.
How to Conduct a CO2 Tolerance Test:
Performing a CO2 tolerance test at home is about measuring how long you can comfortably hold your breath after exhaling, which indirectly indicates your body’s tolerance to rising CO2 levels in your body.
- Sit in a comfortable position.
- Take a few minutes to relax and breathe normally – inhale and exhale effortlessly though your nose, don’t change your usual breathing pattern.
- Take one breath in through your nose (not a very deep breath) and exhale slowely and comfortably through your mouth (don’t force all the air out).
- Start a timer after you’ve exhaled.
- Hold your breath after exhaling, for as long as you comfortably can.
- Comfortably means – the goal isn’t to push yourself to the absolute limit but to see how long you can hold without feeling a strong urge to breathe.
- Finish the Test:
- As soon as you feel the first urge to breathe, stop the timer on your phone.
- Record the time. This is your CO2 tolerance time.
- With a normal inhalation, this version of test may be slightly less challenging than after a deep inhalation, but it still gauges your body’s CO2 tolerance effectively.
There are other 2 different protocols of CO2 tolerance test:
- CO2 Tolerance Test After Deep Inhalation: Take a deep breath in and then slowly exhale. After a full exhale, hold your breath and measure the duration until a first strong urge to breathe. The time from the end of the exhale until the urge to breathe is recorded. This method emphasizes lung emptying and measures tolerance as CO2 builds in the system.
- CO2 Tolerance Test During Slow Exhale: After taking a deep or normal inhale, start exhaling very slowly, trying to prolong the exhale as much as possible.
The duration of this slow exhale is recorded. This version of the test focuses on control and prolongation of the exhale, which can be a measure of both CO2 build-up tolerance and diaphragmatic control.
Interpreting the CO2 tolerance score:
- Less then 20 seconds: your CO@ tolerance should be improved
- 20-40 seconds is the average time most people can achieve
- 40-60 seconds indicates a very good Coz tolerance and is above average.
- 60 seconds and more: great breath control and Coz tolerance, good respiratory health and good response to stress.
Both tests CO2 and BOLT offer insights into CO2 tolerance and your breathing efficiency:
• On one hand the CO2 tolerance test emphasizes the body’s response to prolonged breath-holds and CO2 buildup
• On the other hand the BOLT test focuses on everyday breathing habits and the initial urge to breathe after a relaxed exhalation.
Balancing Oxygen and CO2: Key Health Benefits
This is a journey, please don’t expect to master you breath-hold and better CO2 tolerance after 2 exercises.
When to expect results?
On average, you can expect cumulative breathing practice benefits in about 3 to 6 weeks, depending on your practice and progress. The balance of oxygen and carbon dioxide influences our physical health, mental wellbeing, and our ability to handle stress.
How can you directly benefit from this innate power of your breath:
Breathe with awareness: Being mindful of your breath, focusing on slow, nose inhalations and exhalations. This helps maintain the O2-CO2 equilibrium.
- Stay Active: Engaging in consistent physical activity of your choice, bolsters lung function and improves the exchange of oxygen and carbon dioxide.
- Control Rapid Breathing: Breathing excessively fast (over 20 breaths per minute) will disturb your O2- CO2 balance. If stress or other factors speed up your breathing, work on slowing it down and always breathe through your nose, not mouth.
- Hydration and Nutrition: Staying hydrated is more than just quenching your thirst, it amplifies your metabolism and fine-tunes cellular exchanges in your body. Also, preferably home-cooked meals, more vegetables. I eat meat and fish, so I won’t advise against it, quality food supplements several times a year and simply being mindful about when and how we eat, chew your food properly, because digestion starts in our mouth and preferably no snacking beetween meals.
- Avoid Highly Polluted Areas: Prolonged exposure to pollution can reduce the amount of oxygen reaching your bloodstream and increase CO2 levels and your body’s balance. I never breathe when I am crossing a busy street, it’s a great way to practice breath-holds(apnea walking) but please, don’t do if you have never practiced mild breath- holds while sitting, I always advise for moderation and a slow start.
So, next time you’re catching your breath after climbing stairs or trekking up a hill, remember that there is a dance of O2 and CO2 happening inside your body.
Understanding this dance enhances your well-being, boost stamina and reduces stress.
The Bohr Effect, BOLT test, and CO, tolerance test reveal this intricate balance, giving us insights into natural powers of our breath.
Every inhalation and exhalation carries with it the potential for better well-being, vitality, focus, stress reduction.
If this resonates with you, comment and subscribe, because every week I will deliver more articles on practical breathing exercises.
As the saying goes, “Practice makes perfect.” So, give these two breathing tests a try and let me know how it went. I will answer.
To Your Breath!