Nasal Respiration Part 3: Challenges (Respiratory Demand)
This week we continue with nasal respiration (NR) and tackle its most relevant and significant challenge, respiratory demand. Last week I discussed another challenge to NR, stiffness demand, or loaded respiration - when one has to breathe and brace simultaneously, e.g. carrying a heavy box from a moving truck into your new home. While there is no doubt that loaded respiration is challenging and must be trained if one is going to be able to master bracing, maintaining NR with increasingly higher respiratory demand is by far the biggest challenge to NR. Such is the focus of today’s article.
As one experimenting with NR quickly finds out, NR is challenging. Many struggle to maintain NR at all, even just sitting on the couch. Now try and maintain NR while doing cardio (walking, cycling, jumping rope, running, etc.) and the difficulty increases more quickly than you might expect. Such was my experience several years ago when I started this journey.
As has been well established, NR is the optimal respiration strategy for everyday life. During quiet, relaxed respiration one should breathe in and out of their nose - not in through the nose, out through the mouth, as is often said. However, once one starts engaging in sport (especially one with a high respiratory demand like cycling, marathon, or Ironman) then, due to increased need for oxygen, mouth respiration (MR) tends to kick in. To get more oxygen, we need to cycle more air in and out through the lungs. For the simple reason that the hole is bigger, MR is better able to accomplish this goal. [Side bar: there is a lot more going on here than just air in and air out, specifically CO2 exchange and its effect on oxygen perfusion, among other things. My focus here is on the effects NR and MR have on one’s stabilizing strategy. If, you’d like to learn more about biochemical mechanics of NR, I suggest reading Patrick G. Mckeown’s book the Oxygen Advantage. End of side bar.] When the oxygen demand rises, and one starts to use MR, this is called accessory respiration because one needs accessory muscles of respiration to meet the oxygen demand. The most (in)famous and widely accepted accessory muscles of respiration are the upper trapezius, the pectorals (major and minor), the levator scapulae, the SCMs, and the scales. What is not widely recognized is the erector spinae’s roll in accessory respiration. This is where whether one is using NR or MR affects one’s stabilizing strategy.
An untoward effect of MR is an increase in the activity of the erector spinae. This perpetuates a pathological stabilizing strategy I call the Extension/Compression Stabilizing Strategy (ECSS); one which uses hyperactivity of the erector spinae and psoas to stabilize the spine. As discussed in the previous 2 articles, optimal stabilization “maximally leverages intra-abdominal pressure (IAP) whilst utilizing as little spinal extensor activity as possible”. Because of the hyperactivity of the erector spinae that comes with MR, therefore, it is not possible to stabilize properly whilst using MR. This is why we must expand the range within which we can maintain NR, so we can more properly more often. Herein lies the challenge.
In sport, we often encounter scenarios where the respiratory demand is high. This encourages the brain to shift from NR to MR. When we shift to MR, we do so at the expense of the stabilizing strategy. If we maintain NR (without training this is) then we preserve optimal stabilization, but are unable to meet the respiratory demand of the task. This is why NR at higher respiratory demands must be trained. To minimize the amount of time we are performing (in both sport and life) with an inferior & compensatory stabilizing strategy perpetuated by MR. So how does one train NR at higher respiration rates - by graded exposure of course.
As with training loaded respiration (covered in the previous article), improving NR during situations with increasingly higher respiratory demand, one needs to start easy and slowly increase the difficulty. The best place to start, assuming one can perform NR while stationary (say sitting in a chair), is on a stationary bike - not walking or running as is often proposed. On the stationary bike, we are able to increase the respiratory demand on the athlete, straining their ability to maintain NR without any significant increase in the stiffness demand (loaded respiration). Another benefit of the stationary bike is that the force output is fairly consistent. You do not have periods of exertion and relaxation that you do with running or rowing. Because the force output is constant and consistent, it is easier to focus on the task at hand, NR. Biking is also not very technically complex, making learning the skill of NR less challenging as it would be when applying it more technically complex activity. Learning two skills at the same time is unproductively difficult. A good example would be trying to learn how to do double-unders and NR simultaneously. You can see how challenging this would be from a motor learning perspective. Using the bike avoids all of these challenges.
When you get on the bike and start to increase your effort, if you pay close attention to the voice in your head, you will notice that at some point it starts saying “open your mouth”. At first, the voice is a quiet, like a whisper, but as you continue to increase your effort, the voice becomes louder and louder until you comply and shift to MR. To increase one’s range for NR, all one has to do is repeated exercise at the point where there is a weak voice telling you to open your mouth and shift to MR. Training at this point feels a little like you are drowning. You are not quite gasping for air, but you feel like you need more than you are getting. As you continue to train at this level of mild discomfort, the subtle panic will subside and you will have to increase the effort to maintain the voice. This process feels more like the brain adapting or recalibrating the panic level as it becomes accustom to using NR in situations with higher respiratory demand. It does not feel like biochemical, endocrine, or structural neurological adaptation. You're just getting used to using NR at that effort level.
While it does’t really matter in the end, if you are a lover of data, monitoring your heart rate (HR) during this process can be interesting. I have taken many athletes and patients through this process and the vast majority of the time, the voice telling them to open their mouth presents in low zone 2 (zone 2 is typically 60-70% of your HR max). The end goal is to train to the level where the voice doesn’t present until high zone 3/low zone 4 (or right around 80% of max HR). If you can do this, you are able to maintain NR well into zone 4 before the respiratory demand is just too high and you must open your mouth. The barrier here has more to do with the structural size of your nasal passages than anything else. It just comes down to physics. At some point, you simply cannot transfer enough air through your nasal passages to meet the respiratory demand. How quickly this structural barrier presents has a lot to do with your anatomy. How large are your nostrils? What’s the diameter of your nasal passages? Do you a deviated septum? Are you a little congested? Each of these will affect your ability to maintain NR during situations with high respiratory demand.
The training regiment that I prescribe for this is doing 5-30 minutes of NR threshold training immediately after your done working out. Your HR is already elevated, so it’s quite easy to get to your NR threshold (where the voice telling you to open your mouth is noticeable, but weak). 3-5 days a week, or every day if you’re so inclined, do 5-30 minutes of NR threshold training and you will notice that the HR (a proxy measurement for respiration rate) at which the weak voice presents will slowly increase. Eventually, the limiting factor is not NR, but metabolic. Holding mid zone 4 HR for 30 minutes is quite uncomfortable. Once you’ve gotten to this point, your NR threshold for respiratory demand is up to snuff.
Best of luck!
- Dr. Richard Ulm