If you’re anything like me, the memory of your very first CrossFit WOD is burned into your lungs.
From the moment that the clock started running until the very last rep of the workout, you likely sucked wind harder than at any previous point in your life. As you fell to the ground afterwards in a heap of exhaustion, a love/hate relationship with the “sport of fitness” developed right on the chalk stained and sweat soaked spot.
What many of us were experiencing was an introduction to metabolic conditioning. This newly coined term describes a high intensity training model designed to, in the words of CrossFit founder Greg Glassman, “increase the storage and delivery of energy for any activity.”
In a 2003 Crossfit Journal article, Glassman shared his position on the importance of metabolic conditioning to “avoid specificity of adaptation allowing for first wave cardiovascular and respiratory adaptations.”
It’s been 16 years since that original journal article was written.
16 years of thrusters, wall-balls and those ever elusive airdyne calories. 16 years of sweat, grit, commitment, and community. A lot of memories and training milestones can be packed into a 16 year time frame.
There are a lot of cardiovascular and respiratory adaptations that can be made as well. One of the greatest physiological adaptations that an athlete can make, however, remains largely untapped in the sports training community. This leaves the door to progress wide open, despite how seasoned and experienced a CrossFit athlete you may be. It is the adaptation that determines how the process of “delivering energy for any activity” that Glassman spoke about 16 years ago actually occurs.
It’s our ability to utilise oxygen more efficiently and more effectively.
Understanding how oxygen is directly related to energy production may mark the next major paradigm shift in human health, fitness and sports performance.
Breathe to perform: the physiology of peak performance
When CrossFit first began, anaerobic output was a glaring weak link in the athletic chain for many athletes. The sport has evolved to the point where this statement might not be true anymore.
Past Games events have demonstrated the effectiveness of CrossFit’s ability to increase work capacity over short duration. High intensity workouts showcase a collective need to perform more aerobic capacity training.
But, what is aerobic capacity? Does it mean just putting in more LSD (long, slow distance) efforts or is it changing the way that our body utilises oxygen to fuel the release of ATP to power muscular activity.
It is possible to put in hours of focused endurance work each week while never making the critical adaptation which allows this process of more effective energy delivery to take place: that process is an increased tolerance to carbon dioxide and must be trained specifically in order to be improved.
Is your breathing holding you back?
Take the following test from the book The Oxygen Advantage by Patrick McKeown to determine whether your breathing is a buried weakness or a hidden strength.
- Take a normal inhalation through your nose
- Exhale gently
- Pinch your nose
- Wait for the first urge to breath and time how long it takes for this urge to occur
Note: This is not a test of willpower or a test of how long you can hold your breath. Once you get the first urge to breathe stop the timer and you will have the information that you need to assess your C02 tolerance.
Was it 10 seconds? 20 seconds? 40 seconds or more?
If you were in a large room filled with athletes performing this test you would find that C02 scores would run the gamut from less than 10 seconds to more than 40 seconds.
What does your score mean, and how does it affect your athletic performance?
A score below 20 seconds indicates a comparatively high level of sensitivity to carbon dioxide which will require you to rely on a higher volume of oxygen during training while needing to offload more C02.
This is an athletic disadvantage when compared to an athlete who can work at higher intensities with an increased ability to utilise C02 for more efficient oxygen transport, instead of ridding the body of C02 prematurely and suffering the cost of “gassing out” as a result.
For every 5 second increase in your C02 tolerance score you can expect to feel more energy, increased stamina, and less fatigue in your aerobic training.
When you exhale and pinch your nose, carbon dioxide levels begin to rise. Your sensitivity to rising carbon dioxide will determine how you will need to breathe during a difficult workout which, in turn, determines your ability to use available oxygen to power those hard working muscles when you need it most.
I strongly believe that the ability to extract and utilise these basic physiological principles will separate the pack in the seasons to come.
Why is optimal breathing such an advantage in CrossFit?
Although variance is a key tenet to the CrossFit training methodology, the WOD is written clearly on the board prior to each training session or competition along with the implicit energy system demands and estimated workout duration for all competitors to study.
A rudimentary understanding of energy consumption and energy demands allows each competitor to make basic decisions about pace prior to the workout beginning. Unlike a sport such as mixed martial arts where the energy demands may be directly dependant on the tactics and approach of your opponent, or a team sport such as basketball where a dynamic interplay between players dictates the pace of the game, CrossFit offers a strategic opportunity that is akin to understanding the basics of accounting.
Oxygen Is Currency. Movement is Expensive.
If you have a $1,000 budget for a 5 day vacation, you would be unlikely to spend $900 of it on the first day. Equally, if you saw a 21 minute workout on the whiteboard you would be unlikely to approach it as if it were a 400m sprint.
Understanding the aerobic and anaerobic demands of each workout beforehand allows you to approach each effort with a heightened level of athletic intelligence.
An understanding of how breathing impacts aerobic and anaerobic performance – and that you can not only control your breathing but significantly improve it – allows you to gain a competitive advantage in your next WOD despite the specific time demands of the workout.
How Oxygen Works: Understanding Aerobic and Anaerobic Respiration
The process of cellular respiration is a complex one. Fortunately, even the most basic understanding of how oxygen fuels muscular activity can provide a distinct advantage in terms of pacing yourself during workouts as well as in the development of stronger breathing muscles and an increased tolerance to carbon dioxide: the secret ingredient when it comes to utilising oxygen effectively and efficiently.
The next time you find yourself bent over with hands-on-knees after a tough set of thrusters, struggling to get air into your lungs, keep the following in mind:
There is no shortage of available oxygen in the atmosphere.
It is your internal environment that has changed due to the intensity of the workout. More specifically, your ability to get oxygen from your bloodstream and into muscles has been diminished.
That’s because the key to unlocking oxygen from the bloodstream is C02 and big breaths taken while exhaling through your mouth are offloading C02 from the body at too high a rate to make efficient oxygen utilisation possible.
Here’s an easy way to remember this next time that you train:
The amount of Co2 that you lose is the amount of oxygen that you can’t use.
The knowledge of this basic physiological process becomes a competitive advantage for any athlete willing to train the following respiratory adaptations in order to master their breathing and improve their aerobic capacity:
- Improve your ability to utilise nasal breathing
- Add carbon dioxide tolerance training to your warm-ups
- Learn how to breathe to recover quicker post workout
The Nasal Breathing Advantage
You happen to have access to the most powerful and effective breathing machine ever created: the human nose.
The nose is designed for the purpose of up-taking oxygen, removing harmful particles from the atmosphere, warming air prior to entering the body and creating a highly pressurised flow of oxygen directly into the lungs and diaphragm. It also induces the release of nitric oxide, a potent vasodilator that widens the walls of your blood vessels creating a more effective pathway for oxygen rich blood to make it to muscles.
It may be smaller than the mouth, but that’s the athletic advantage. If getting more oxygen into our bodies were the solution to avoid “gassing out” in workouts we would simply take bigger breaths. However, oxygen is in no short supply.
The ability to “use” available oxygen i.e, extract it from the hemoglobin in the bloodstream, which is the job of carbon dioxide, is the challenge that we face when training.
Nasal breathing allows us to increase our oxygen utilisation while decreasing the amount of C02 that we offload while training.
Keep in mind that C02 is not simply a “waste gas,” it is like oxygen’s teammate in a partner WOD. They work together and if one bales out, the other’s performance suffers.
Breathing through the nose can initially be difficult for many athletes. Therein lies the advantage for those willing to train the adaptation.
After a few weeks of consistent training, many athletes can perform at upwards of 90% max heart rate with nasal-only breathing. They uptake oxygen faster and more effectively and delay premature transitions into anaerobic respiration which come at the cost of increased metabolic waste to buffer.
They also remain fresh so that, if they do decide to shift to mouth breathing near the end of a workout in order to sprint to the finish, they are positioned for a powerful finish.
Two simple exercises to improve Co2 tolerance, nasal breathing capacity and aerobic performance
- Inhale normally
- Exhale fully
- Sprint as far as you can on a breath exhale
- Recover and repeat 3 times.
Use an assault bike, rower or ski erg and try the following 4 minute warm-up.
EMOM for 4 minutes:
Nasal breathing only. Put out as much wattage as the prescribed breathing cadence allows.
- Minute one: work to a 4 second inhale/4 second exhale breathing cadence.
- Minute two: work to a 4 second inhale/ 6 second exhale breathing cadence.
- Minute three: work to a 5 second inhale/5 second exhale breathing cadence.
- Minute four: work to a 5 second inhale/7 second exhale breathing cadence.
Before long you will be able to increase the wattage while sticking to the prescribed warm-up breathing pattern.
This is akin to doing pull-ups and push-ups for your breathing muscles while making the physiological adaptations to carbon dioxide that help separate you from the pack and break through those PR plateaus that we’ve all experienced.
Additional Training Tips
- Limit mouth breathing throughout the day. If you can get through these warm ups with nasal-only breathing you definitely don’t need to breathe through your mouth while sitting at a desk. Doing so will lower your Co2 tolerance.
- Dedicate a portion of your training to increasing aerobic capacity and improving your ability to breathe through your nose. Don’t be afraid to fall off of the “leaderboard” in these workouts. Commit to taking a step backwards in place for a few weeks in order to take a huge step forward in work capacity in the long run.
Recovery breathing: optimising post workout recovery
How you breathe post-workout will affect how quickly your heart rate returns to baseline levels as well as how effective your post-workout mobility session will be (you can’t “relax” a body that is still in a high-stress state).
Your ability to recover more effectively sets you up for success in your next training session. This simple post-workout breathing exercise can help you optimise your recovery and get the most from your hard work:
- Step 1: Take 4 “blow-off” breaths. Inhale through your nose, take a big breath out through your mouth and repeat 4 times. Following your workout, C02 levels are still exceptionally high, yet the body’s immediate oxygen demands are comparatively reduced. Getting rid of some excess Co2 is a great start to an efficient post workout recovery process.
- Step 2: Return to nasal only breathing when you are able. Don’t rush this process. Simply be mindful of your breathing and soon you’ll be able to control your inhales and exhales again.
- Step 3: Once nasal breathing is comfortable, attempt breathing to a 4 second inhale and 4 second exhale. Again, don’t rush. Once you can do this comfortably proceed to add a 4 second hold at the top of your inhalation for a 4/4/4 recovery breathing pattern. Notice how you feel, how your heart rate responds and how much better the foam roller feels when you’re not ready to puke.
As a CrossFit athlete, you train your body and you push it hard. You’ve most likely already made nutritional changes to support your training and you’ve worked to prioritise sleep to support your recovery. You’ve looked at the various pieces that make up the training puzzle and you’ve worked hard to put each one in place.
It just so happens that one of the most important puzzle pieces may have been right underneath our noses the whole time…
Training comes down to getting oxygen to the body when it needs it most. No amount of willpower or dedication can outweigh the most basic and essential demands of our physiology. The more effective we become at using oxygen to fuel our athleticism, the higher we can raise the ceiling of our own performance’s potential.
David Bidler is a writer, speaker, and performance-breathing coach living in Portland, Maine. David owns The Distance Project: Strength and Conditioning. Follow him @the_distance_project on Instagram.