Improve Your HRV: Breathing at Resonant Frequency
Improve Your HRV: Breathing at Resonant Frequency
Level 4: All-Star
Welcome Players! First, we learned about what HRV is and how it’s measured in Heart Rate Variability: A Primer. Then, we went over all the major lifestyle choices and habits that affect HRV on a long-term basis in HRV: Optimize Your Life. And today, we’ll be revealing the scientifically proven strategies that you can implement immediately to begin to improve your HRV indices. Are you ready? Let’s go!
Contents:
Long Term > Short Term
Resonance Breathing
Biofeedback
Getting Started
From Beginner to Beyond
Conclusion
Long Term > Short Term
I know, I know. You wanted me to get right to the good stuff. But I’ve got to make my last soap-box stand on why this article is not even half as important as the last one (Optimize Your Life).
Sustainability. Plain and simple.
I’ve worked with literally hundreds of professional athletes, across a dozen different sports, each with their own highly specific demands. A professional race-car driver sits trapped in a cockpit for sometimes 4-hours at a time fighting G-forces with a HR that’s sustained at nearly 90% Max HR. A professional golfer has no more than 120 seconds to precisely hit a golf ball to within mere feet of the hole from hundreds of yards away. Both are no easy task. Both require an optimized HRV if they want to play (or race) at a high level for a long time.
The key is for a long time. HRV, for all the reasons explained prior, is not a good way to gauge performance based on singular point in time. We can’t take the HRV from the golf player and race-car driver during their sport and tell you who’s a ‘better athlete’ or who has a better chance at winning their respective competition.
In the span of an athlete’s career, you’re going to have hundreds if not thousands (baseball) of competitions. What we want to do, with this in mind, is implement all the strategies where you get the greatest return over the longest period of time first. Then, you can spend time and energy on optimizing shorter time-frame strategies.
Not only will this approach ensure quality performance over the long-term acting as a natural buffer against short-term performance decrements, but it will allow a synergistic effect of the improvements provided by the short term techniques.
In short, don’t take the easy path. Don’t just do drills for HRV training and call it a day. Don’t do the least amount of work possible and expect the most amount of improvements.
Do it the right way. Do it the (slower) sustainable way. Do it with intention of progress, not perfection. Do it by stacking positive short-term strategies on top of long-term habits.
And what do you do exactly?
Well, after you’ve gotten a consistent and healthy sleep habit, found a nutrition diet that’s right for you, train for higher intensities for shorter periods of time, stayed away from harmful substances and negative emotions, and pursued your goals in a direction that was positive to your mental health, there’s only one thing left to do:
Breathe.
Resonance Breathing
Now that the cat is out of the bag, we can finally talk about the most efficient and effective breathwork technique (if you can even call it that) that promotes a higher HRV and influences the parasympathetic nervous system greatly.
Resonance breathing is achieved when there is synchrony between heart rate oscillations (RSA) and respiratory rate. This occurs at a resonant frequency, in which most people will occur at 0.1hz (= 6 breaths per minute).
Let’s clarify the “for most people” before we go any further.
This study looked at respiratory rates of 3, 4, 6, 8, 10, and 12 breaths per minute against HRV metrics. They found that the greatest positive effect of HRV occurred between 4-6 breaths per minute. Here are the results: 1
You might wonder, how can the greatest improvement occur between 4-6 breaths per minute?
Well, because of the ways you measure HRV, it depends on which specific metric you were using to gauge overall HRV influence. You can see in the graphs below measures of amplitude at each respiratory rate and amplitudes of peak power in HRV. Some of this data even includes positive effects at 3 breaths/min.
So which respiratory rate is best?
Hold on, back to resonance breathing. Almost there…
One of the biggest indicators of total HRV efficiency is the LF power band. The higher the LF amplitude the greatest effect your HRV will enact between the cardiovascular system and respiratory system. If you’re looking at respiratory rates and want to know which has the greatest effect on HRV (which increases the LF amplitude the most), then the answer is 4 breaths per minute!
But human physiology could never be that simple. The greatest machine ever made has a lot more components than a simple breathing rate of 4.
You’ll also notice in that study there was not a test group for 5 breaths per minute, or 5.5, etc. So we don’t directly know exactly which respiratory rate is the best.
But we will never be able to tell from a group study like that. We have to dig deeper, and evaluate at the individual level.
In my explanation of resonance breathing I said most people this occurs at 0.1 hz (6 breaths per minute). That’s because every individual has their own unique RSA, to where resonance frequency will vary.
Resonance frequency is the frequency at which the synchronization between RSA and respiratory rate is greatest for that individual!
That means that some people may find their resonance frequency to be at 4 breaths/min, some 5, 5.5, or even 6 breaths/min. Every one will have their own physiological preference as to which respiratory rate has the greatest impact on their autonomic nervous system, and it is possible for this to slightly alter over time.
Does it really matter if you’re breathing at your specific resonance frequency vs. just using the standard norm of 5.5 breaths/minute? Yes, yes it does.
This study wanted to know the answer to that very question, and took 96 participants through a resonant frequency evaluation test (yes, I will tell you how to do this) where they found each participants resonant frequency. They then split the participants into 3 groups:
Breathing at measured resonance frequency (RF)
Breathing at measured resonance frequency +1 breath/min (RF+1)
Control group “sat quietly with their eyes open” (experimental version of timeout)
This is what they found:
As you can see, the RF group had the greatest LF/HF ratio response. To this point we’ve only talked about LF and HF individually, so I’ll add here that the LF/HF ratio can be thought of as the ratio of parasympathetic to sympathetic influence. The higher the ratio reflects higher parasympathetic dominance (seen in calm states) and and lower ratio reflects higher sympathetic dominance (as seen in fight/flight scenarios).23
Finding and breathing at your specific resonance frequency is important to maximize the beneficial effects of practicing resonance breathing for improved HRV.
How do I find my resonance frequency?
The first thing you’ll need is a way to accurately measure short-term indices of HRV. To my current knowledge the most common wrist/finger wearables that track sleep and HRV over a 24h period are not sufficient to record short-term changes via a breathwork intervention.
Coaches note: I am personally in talks with a company who has produced an accurate way to measure short-term HRV. Unfortunately I can’t reveal this company until things are finalized, but if all goes well I will be able to provide all my readers with a significant discount on the product. I will update this post and send out an email when these discussions are finalized.
Other than an ECG from a physiology lab, I am not aware of any other commercial products that have demonstrated accurate measurements of short-term HRV indices (<5 min). Fingers crossed that I will be able to provide you all with access to a good product soon.
Here is how you would test to evaluate your personal resonance frequency:
Utilizing a metronome or visual breath pacer, start recording via an HRV measurement device (TBD) at a respiratory rate of 7 breaths / minute.
Breathe at this pace for 2 min.
At the end of 2 minutes, take a break and breathe normally for a 2 minutes.
Set your breath pacer for 6.5 breaths / minute, breathe at this rate for 2 minutes.
Rest - breathe normally for 2 minutes.
Set pacer for 6 breaths / min. Breathe at this pace for 2 min.
Repeat this process of breathing at a set pace for 2 minutes, incrementally decreasing the respiratory rate by 0.5 breaths/minute until you get to 4 breaths / minute with a 2 minute normal breathing rest in between.
At the end of this process you would use the data captured from your HRV measurement device and use either the LF amplitude or LF/HF ratio to determine at which respiratory rate your body has the greatest physiological response. This is your resonance frequency!
Ok, so you’ve got your resonance frequency. Now what?
Biofeedback Training
Biofeedback training is pretty much exactly as it sounds - utilizing a form of feedback to contribute to the internalization of an action or process relating to human biology.
In its simplest form, HRV Biofeedback Training occurs by using a visual breath pacer to moderate respiratory rate with heart rate. In more advanced forms, it includes visual feedbacks relating to the depth of movement of the ribcage (indicative of diaphragmatic involvement and volume of inspiration) and actual HRV metrics themselves.
Below is an example of a simple breath pacer:
A breath pacer is good, but it only provides information on the respiratory rate. A more complete biofeedback device would include heart rate and changing spectral analysis of inter-beat interval or a continual average of LF HRV. An example of this would look like:
The more information we can use as feedback to modulate our respiratory rate’s synchrony with heart rate the more we’ll be able to influence it via training.
In the above image, the goal during a training session would be to have your respiratory rate and depth of respiration (blue line) match the pacer (green line) with your short-term HRV indices (red line) matching or occurring slightly before the pacer. You’d be surprised at how much influence you can exert over your autonomic nervous system with access to how it’s performing in real time.
Breathing at your resonance frequency while incorporating biofeedback has drastic effects on promoting all the positive effects of a higher HRV. You are literally training your HRV to be higher!
"HRV Biofeedback training reliably increases HRV, mood, and adaptability." 4
"…the results suggest that HRV biofeedback is a highly promising intervention for reducing anxiety and stress." 5
"The results of this review provide evidence that HRVB… have positive effects on a variety of physical, behavioral, and cognitive conditions." 6
"Our findings suggest that HRVB is an effective intervention for the reduction of depressive symptomatology… Interestingly, HRVB intervention is effective also in the treatment of anxiety and perceived stress, with a high reduction of symptoms in treated groups compared to controls." 7
Getting Started
We’re finally here! If you’ve made it this far you’ve learned more physiology as it relates to HRV than 95% of the population. You’re equipped with the right information as validated by the scientific literature, and have a full understanding of the context that our scenarios occur in. You’re ready to begin a dedicated breathwork program focused on improving HRV, granted of course that you’ve already started to make any necessary changes to your lifestyle habits to promote a long-term, sustainable improvement in HRV.
What do you do first??
Assuming you don’t have a way to accurately measure your HRV (yet!), the first place you start is with a paced breathing protocol of ~5.5 breaths per minute, using either a visual or auditory feedback.
Coaches note: I know I said that you should find your resonance frequency and not just subscribe to the norm of 5.5, but you won’t have a way to find your resonance frequency until you get an accurate way to measure HRV, and that is no excuse to delay. Breathing at 5-6 breaths/min will help anyone begin to improve their HRV, and the next steps will be to hone in on your resonance frequency and practice at that respiration rate for pure optimization.
There are a plethora of apps and videos available online that allow you to select a respiratory rate and provide visual feedback to guide your breathing pace. Find one that pleases you the most.
Settings to start:
5s inhale, 1s hold, 5s exhale, 1s hold
The hold’s end up becoming more like brief pauses between the transition of inhale/exhale, and produces a breathing rate of 5 breaths per minute.
Practice for 5-15 minutes a day (shooting for 10 minutes is a good benchmark)
That’s it. It really is that easy.
Understanding why you’re doing it this way, how your respiration rate, depth of respiration, and heart rate all influence your HRV, is crucial to using the feedback to make adjustments going forward. You’ll notice that after even a 10 minute session, you feel more calm, balanced, and the ease at which your breathe is increased. The longer you continue to practice over time the more these effects will carry over into your day-to-day life.
For even more improved effectiveness, keep a breathwork journal. Before you begin your HRV Training practice, write down how you feel, what emotions are related to your current state, and anything that you think had an impact. After you’ve done your session, write down the same: how you feel, what emotions are related to your current state, and any thoughts or influences that you had while in session. Reflect often on the physical and psychological changes that come as a result of your breathwork practice.
Homework (?!?)
Yes, you do have some homework. Reading, learning, and understanding material is important, but your level of comprehension does not matter if you do not take what you learned and apply it.
So let me be the nudge you need, and implore you to start a HRV Breathwork training program today. Or right now!
Here’s what you’re going to do:
Click on this link to go to a free breath pacer
Set it to 5s inhale, 1s hold, 5s exhale, 1s hold
Set a timer for 5 minutes, hit start, and follow the line!
Go! Right now! The best time to start your HRV training was yesterday, the second best time is right now…
After you’ve given it a shot, please come back here and drop us a comment on how you felt! What did you notice? How was the experience individual to you?
Coaches note: While my earlier recommendations are to start at a 5s inhale, 1s hold, 5s exhale, 1s hold, this is by no means an absolute starting point. This is what I gravitate towards personally because there is a natural pause when transitioning from an inhale to exhale, and I’ve noticed that accounting for this pause through the use of a 1s “hold” allows me to breathe without restriction. You can play around with the settings, opting for a 5s inhale/exhale or 5.5s inhale/exhale without holds to see which one your physiology is attracted to most.
Disclaimer: This is not medical advice. The content is purely educational in nature and should be filtered through ones own lens of common sense and applicability.