chemoreflexes

A Helpful Breathing Tip, Two Ways, and How to Build a Stronger Mind


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4 THOUGHTS


1. The Most Helpful Breathing Tip I’ve Found (it’s embarrassingly cliché & simple)

Don’t take ten breaths. Take one breath, ten times.

Don’t do 5 minutes of breathing. Consciously take one breath, over and over, until your 5-minute timer goes off.

Sounds silly, but it works 👏

2. How to Build a Stronger Mind

In Peak Mind, Dr. Jha describes a “mindfulness push-up” as the following:

  1. You shine your attention on your breath.

  2. Your mind wanders, and you notice it.

  3. You redirect your mind to your breath.

“This is what we might call the ‘push-up’ of a mindfulness breathing exercise.”

I love this analogy because it conveys the most crucial aspect of mindfulness: Just like repeated physical push-ups make our muscles stronger, repeated “mindfulness push-ups” make our minds stronger.

Meaning we need our minds to wander so we can notice it and come back to the breath. It’s how our minds get stronger.

3. Breathing Must Be Practiced Not Just in Solitude

“Spirituality must be practiced not just in solitude but also among people. Open up to people around you and feel connected. This is the true challenge of spiritual practice.”

- Haemin Sunim, The Things You Can See Only When You Slow Down

The same is true for our breathing (or any contemplative) practice. It must be performed not only in solitude, but in real life:

  • How we do (or do not) reply to comments on social media is our practice.

  • How we do (or do not) reply to emails that provoke us is our practice.

  • How we do (or do not) interact with friends & family is our practice.

  • And on and on for every aspect of our lives…

So, this is the true challenge: To use our favorite contemplative practice to fundamentally change who we are and how we interact with the world for the better.

4. Two Ways to Keep Your Practice Interesting

  1. Switch up your routine or exercises every 15-30 days to continuously create novelty.

  2. Cultivate mindfulness so the same old boring exercises continuously create novelty.

P.S. There’s no right or wrong, and you can use both approaches simultaneously 😊


1 Quote

Practicing to walk and breathe mindfully helps you dwell more in the real world, so you can get in touch with the wonders of life in the present moment, and nourish and heal your body and mind.”
— Thich Nhat Hanh

1 Answer

Category: Breathing Basics

Answer: The way your breathing responds to high carbon dioxide or low oxygen is generally referred to as this.

(Cue the Jeopardy! music.)

Question: What is chemoreflex sensitivity?


In good breath,

Nick Heath, T1D, PhD
“Breathing is the compound interest of health & wellness.”


P.S. Every single morning


* An asterisk by a quote indicates that I listened to this book on Audible. Therefore, the quotation might not be correct, but is my best attempt at reproducing the punctuation based on the narrator’s pace, tone, and pauses.


 

Two Regulatory Effects of Breathing (+ James Nestor Breathing Q&A)

 
 

Waste no more time arguing what a good man should be. Be one.” - Marcus Aurelius

 
 
 

You probably hate Zoom meetings by now. In fact, if you work in an office setting, you’re probably just tired of meetings in general. But every now and then, you have a truly important meeting. You prepare, rehearse, read, dress nice, and do everything you can to show up ready. 

Physiologically, we step into one of these “truly important meetings” approximately 25,000 times per day…no big deal, I know :) And we can choose how well we prepare for each one. We can send messages of calm, focus, and relaxation, or messages of anxiety, stress, and arousal.  

Whichever we choose, the messages we send with our breathing regulate many aspects of our health and well-being.  

How? Well, the answer to that is complex because breathing interacts with many systems of the body simultaneously (as we learned last week). But, the paper I am sharing this week goes through two significant regulatory effects of breathing.

 
 

 
 

Modulatory Effects of Respiration

Published in Autonomic Neuroscience: Basic and Clinical (2001)

Click Here to Read the Full Summary

 
 

 
 

The two main takeaways from this study are:

(1) Breathing modulates the cardiovascular system through respiratory sinus arrhythmia  

(2) Specific breathing patterns can reduce our chemosensitivity to carbon dioxide and hypoxia


1. Breathing and the Cardiovascular System

Respiratory sinus arrhythmia (RSA) measures how breathing, heart rate, and blood pressure all interact. Put simply, RSA is the increase in your heart rate as you inhale and the decrease in your heart rate as you exhale. RSA is thought to be an index of vagal activity and direct measurement of heart rate variability.  

When we breathe so that the length of our inhale matches our heart rate increase and our exhale matches our heart rate decrease, we maximize RSA. Typically, this occurs when breathing at around 6 breaths per minute. This coherence among breathing and heart rate maximizes heart rate variability and improves cardiovascular efficiency.

 

2. Breathing and Chemoreflexes

They reviewed a study conducted with yoga trainees and non-yoga trained participants. This study assessed how different breathing protocols affect sensitivity to high carbon dioxide (hypercapnia) and low oxygen (hypoxia). These sensitivities are known as chemoreflexes.

As we might expect, the chemoreflexes of the yoga practitioners at baseline were much lower than the non-trained participants. This means their breathing did not increase as much when exposed to hypercapnia or hypoxia.

Interestingly, when breathing at 6 breaths per minute, the controls' chemoreflexes decreased to levels similar to the yogis.  Therefore, the simple act of slow breathing reduced chemosensitivity to carbon dioxide and hypoxia, regardless of previous training.

Being able to tolerate changes to carbon dioxide and oxygen easily is a sign of respiratory and physical resiliency. And merely slowing down your breathing can improve this resiliency almost immediately.

 

How Will Your Next Meeting Go?

Breathing is fascinating because it’s both autonomic and under our control. Obviously, we can’t control every breath we take, and I think that would be an awful way to live.  But, we can deliberately set aside time to harness what we’ve learned from this study.  

Just a few minutes of slow breathing at around 6 breaths per minute can improve chemosensitivity and align your cardiovascular and respiratory systems.  This will help make the other 25,000 odd breaths you take that much more effective.

Here’s to being the regulator of our health and well-being.

In good breath,
Nick

P.S. I would be the first one captured.

 

James Nestor Q&A

James Nestor is holding a “Breathing Q&A,” where he is rounding up questions related to all aspects of breathing to sending them to be answered by experts in the field of respiratory science. I have a few to submit…you should too!

Learn More Here.


Yoga & Breathing Virtual Workshop

My wife is teaching a masterclass on breathing and yoga as part of a larger Virtual Yoga Festival. She’s mixing in slow breathing, CO2 tolerance, Oxygen Advantage, and The Art of Breath. I don’t “advertise” in my newsletter, but the studio hosting the event is donating all of the profits to No Kid Hungry. So if you’re into yoga and/or breathing, you can learn and support a good cause at the same time.

Learn More Here.



 

Lack of Oxygen Might be the Root Cause of Diabetic Complications

 
 

Since we cannot know all that there is to be known about anything, we ought to know a little about everything.- Blaise Pascal

 
 

 
 

People with diabetes are at an increased risk of cardiovascular and autonomic problems. Diabetics also display altered respiratory control, for example, showing depressed (or enhanced) chemoreflexes.

However, previous studies have never examined these two aspects in an integrated fashion.

Integration Over Isolation

The problem with separately studying these systems is that the results might not be independent. For example, if a study shows that diabetics have decreased respiratory control, it might conclude that this is from diabetic nerve damage.

Likewise, if a study shows that cardiovascular function is depressed, it might also conclude that this is due to diabetic nerve damage.

However, if we study them together, we might find that there is a reciprocal relationship. Maybe the respiratory problems are causing cardiovascular issues? Perhaps it’s the other way around?

This study takes that approach and has some pretty remarkable conclusions.

Integrated cardiovascular/respiratory control in type 1 diabetes evidences functional imbalance: Possible role of hypoxia

(Click Here to Read Full SummaryI don’t say this often, but please read this one if you have diabetes)

Published in the International Journal of Cardiology, 2017.

In forty-six type-1 diabetics and 103 age-matched controls, they measured baroreflex sensitivity (BRS) as a marker of cardiovascular function and chemoreflexes as a marker of respiratory control.

Chemoreflexes estimate how sensitive you are to increasing CO2 (hypercapnic chemoreflex) and decreasing O2 (hypoxic chemoreflex).

The Hypothesis: If BRS and chemoreflexes are reduced, this would suggest diabetic nerve damage. However, if some are reduced while others are elevated, this reciprocal relationship might be showing autonomic dysfunction instead of diabetic nerve damage.

This is such an important distinction. “Damage” implies that the damage is done. “Dysfunction” implies that we could make it functional again.

Diabetics Have Worsened Cardiovascular and Respiratory Control

The results showed that subjects with diabetes had a lower BRS than the controls. They also had a suppressed hypoxic chemoreflex. However, they had an elevated hypercapnic chemoreflex. (Remember their hypothesis: if it was nerve damage, both of these chemoreflexes would be reduced.)

Interestingly, the diabetics also showed a lower oxygen saturation. And, they also had relatively high HbA1c’s (an average of 8.19%). A high HbA1c will decrease oxygen delivery to the tissues and cells.

Tissue Hypoxia is at the Root of Diabetic Complications

The reduced oxygen saturation and high HbA1c suggest a resting state of tissue hypoxia in diabetes. Over time, we become “numb” to this, which explains the decreased hypoxic chemoreflex.

The body compensates with an up-regulated hypercapnic chemoreflex, which leads to chronic activation of the sympathetic nervous system (fight or flight).  Chronic sympathetic activation then suppresses our cardiovascular control.

It’s a vicious cycle with negative long-term implications:


 
 
Root_of_Complications_Cycle.png
 
 

Dysfunction, not Damage: A Silver Lining

“We show in the present study that what is normally called ‘autonomic neuropathy’ could be in many cases a functional condition of sympathetic activation, driven by many factors, one of which seems to be resting hypoxia.”


This is all actually good news.  Their results suggest that diabetic autonomic imbalance is mainly functional and not related to nerve damage.  In fact, the authors suggest that this imbalance likely leads to nerve damage, rather than being the result of it. Therefore, therapies targeting cardio-respiratory control could help reverse/prevent diabetic complications if caught early enough.

Break Out Your Slow Breathing Hammer

What are these therapies? One is slow breathing. Slow breathing will immediately improve cardiovascular and respiratory reflexes. It will also enhance oxygenation (when breathing through the nose).

I hate sounding like all I have is a “slow breathing hammer,” but it is just too important not to stress over and over again.

Here’s to taking the first step toward protecting our long-term health as diabetics.

In good breath,
Nick


P.S. A great podcast was recently released with James Nestor, author of the soon-to-be-released book: “Breath - The New Science of a Lost Art”. (The book looks terrific, so I pre-ordered my copy about a week ago.)

You can basically learn everything you’ll ever need to know about breathing in this quick 35-minute interview. I loved it.

Listen to the podcast here.

 
 

Two Simple Ways to Improve Your Sleep Tonight

 
Walk_With_Purpose_Dickens.png
 
 

Charles Dickens just walked into a hotel room. The year is 1860. As arguably the most famous author alive, you might think he set up his writing station and poured a glass of Brandy. Instead, he pulled out his compass and rearranged the place [1].

Dickens’ Odd Fix for Insomnia

Dickens believed that sleeping with his head toward the north helped with his insomnia. This sounds funny but is probably more helpful than his previous solution, which was to walk all night, sometimes covering up to 30 miles [2].

Although Dickens’ sleeping habits were peculiar, it was his keen observations of others that changed sleep science.

Joe’s Snoring and Sleep Science

In 1836, Dickens began writing The Posthumous Papers of the Pickwick Club, also known as The Pickwick Papers. In it, Dickens’ character “Joe” displayed all of the classic characteristics of sleep apnea. Joe was always tired, he fell asleep during the day, and he snored loudly.

Sleep scientists credit this work as being the first accurate observations of sleep-disordered breathing [3], recording it 120 years before the science caught up.

Modern Sleep Science Catches Up

Today, estimates of sleep-disordered breathing are, well, breathtaking. The term “sleep-disordered breathing” itself is rather generic. It covers a wide range of issues related to sleep and breathing (most commonly, obstructive sleep apnea).

However, in 1996 a review study was published that sheds light on the mechanisms that cause sleep-disordered breathing. This research helps explain why it is so common and provides suggestions as to what we can do about it.

Sleep and Breathing State-of-the-Art Review: Sleep-Induced Breathing Instability

(Published in Sleep in 1996 — Click Here to Read Full Summary)

The main conclusion from this study is that your breathing system does not work the same during sleep as it does during wakefulness.  

For example, there is less input to the muscles that keep your upper airways open, which can narrow or collapse them. This narrowing of the upper airways also increases breathing resistance. Additionally, sleep dampens the chemoreflexes that usually keep blood pH in a tight range. 

Interestingly, this “State-of-the-Art Review” concluded that carbon dioxide (CO2) could potentially help with sleep-disordered breathing. CO2 could stimulate the chemoreflexes that keep breathing steady. Additionally, CO2 is a smooth muscle dilator, which would help increase blood flow to the muscles that keep the airways open.

Two Ways You Can Start Tonight

1. Tape Your Mouth

You can start adding CO2 to your breathing tonight by taping your mouth during sleep, which will reduce breathing volume and increase CO2.

Paradoxically, while nose breathing increases resistance during the day, it reduces upper airway resistance during sleep. This small change will help you breathe better during sleep and wake up feeling refreshed and energized.

2. Breathe Less During the Day

You can also practice light breathing during the day to train your body to tolerate more CO2. By doing this consistently, you can reset your baseline CO2 back to normal values and ultimately improve your breathing during sleep.  

In good breath,
Nick

P.S. I think we all need a smile like this right now.

References

[1] Source: https://www.pharmaceutical-journal.com/opinion/blogs/how-dickens-got-a-good-nights-sleep/11074673.blog (I made up the little hotel story to go with it…he might have in fact poured some Brandi too…)

[2] Source: https://academic.oup.com/sleep/article/15/3/264/2749285 

[3] Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3365094/