Breath Rate Monitor

I just upgraded to a Garmin 530 and I see on Garmin Connect that there is a graph showing my breath rate. I heard Nate mention that it would be a good extra datapoint for the Adaptive Training feature, but he spoke of it as if there are no devices measuring this.
It looks as if the new Garmin chest strap measures this but Trainer Road does not record this datapoint.

I think he’s right that there aren’t any devices directly measuring this - it seems that Garmin is inferring respiration rate indirectly from HR variability data:

I think whoop used the same functionality, marketed it as a potential early sign of COVID related illness.

Heart rate variability usually correlates well with breathing at rest for healthy people so it should work at rest. I’m not sure how consistent this is during strenuous exercise. There will be a difference when you get dehydrated, as this will affect the heart’s preload. I wonder if pubmed has something.

I got this article The Effects of Submaximal and Maximal Exercise on Heart Rate Variability - PMC
It looks like HR variability reduces drastically during high intensity exercise. So the Garmin respiratory rate measurement is probably not very accurate during exercise.

Only during your sleep does it display your respiratory rate

Yes sorry, but then that’s the only time it records (or at least gives you the reading from) your hrv values so goes hand in hand.

I looked into this last year when I got a 830. It is most commonly calculated based on a sympathetic vaso vagal response when you breath when measuring from a chest HRM. Sorry, I would post a link but a really quick search didn’t immediately turn up what I read last year.

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Well if it’s accurate and you have a good way of estimating VO2 you could for sure nail where your VT1 is. I don’t know of a good & inexpensive way to estimate VO2, though! Just throwing that out there, though…lot of people want to know what their VT1 is. Here would be an obvious way to know for sure what VT1 is.

But I guess if you have a way to accurately measure VO2 you don’t need a way to estimate respiratory rate. So maybe I’m really just posting this because I like to type. :smiley:

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FWIW, here are charts of my power, heart rate, and respiration rate for Avalanche Spire. Seems to track pretty well for me. Data was collected using a Wahoo Tickr X paired via Ant+ to a Garmin Edge 830. The dips in respiration rate occurred when I took a big drink and one back pedal during the end of the fourth set.

Have you taken data while resting while manually calculating your respiratory rate?

It seems like it would be easy enough to design a chest strap that detects stretching as a means of detecting respiratory rate.

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From the Firstbeat website

What Is Respiration Rate?

Respiration rate describes how often you inhale and exhale in a minute. It is also a primary vital sign along with heart rate, blood pressure and body temperature. Resting respiration rates are typically between 12-20 times per minute during rest and can be around 40-50 times per minute during intense physical activity. This increase in respiration rate reflects the increased oxygen demand of producing aerobic energy.

  • Familiarity with your body
  • Monitor changes over time
  • Recognize when your working harder than normal

How Does It Work?

Each breath you take is coded into your heart rate variability (HRV). The length of time between consecutive heartbeats shortens slightly as you inhale and lengthens as you exhale. The term for this biological phenomenon is respiratory sinus arrhythmia (RSA).

The ability to analytically extract respiration rate from HRV data depends on accurate heartbeat data. The degree to which one’s heart rate changes from one beat to the next can be a matter of milliseconds. Challenging monitoring conditions related to the performance of physical activity mean that the pinpoint accuracy needed for this analysis is only achievable using a chest strap type heart rate monitor.

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Hi Brennus. Finding VT1 is exactly why I need resp rate, but the resp rate graph on Garmin Connect is all over the place. I am interested in polarized training and my goal is to do a 350km MTB ride at the end of the year. My game plan is to do bucket loads of riding just below VT1 and then once a week do what ever I can tolerate for 8min x 4 with 2min rest once a week. So knowing VO2 is not that important I just do the intensity for this session as hard as I can tolerate.
These sweet spot intervals a few time a week seems to stress me out. I don’t mind doing long indoor or outdoor rides at endurance level and do one very heavy interval session once a week.

@aglrocher first of all I think your game plan sounds solid! :wink:

When I say VO2 I mean really the amount of oxygen being consumed at any point in time. VT1 is easy to find (for me, anyhow) if you know your respiration rate and the amount of oxygen you are consuming during an incremental ramp test. You just watch the ratio of those two over time…it stays constant until you reach VT1 then the ratio will ramp up.

In other words, after VT1 respiration rate starts to increase much more than oxygen consumption. It’s super, super obvious when you look at the data! Not like VT2 where three people can look at the same data and come up with a little different number.

But you don’t need to know exactly what your VT1 is…you just need to know that you’re comfortably UNDER it. For me VT1 happens at or around 75% of peak HR pretty consistently so if I cap heart rate at 65% I always feel like for sure that’s under VT1. If you use that target and make sure you’re conforming to the talk test you’ll be good!

GOOD LUCK ON YOUR RIDE! Sounds like it’s gonna be awesome.

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Interesting. Thanks for posting this.

I am not saying this is how it is done in this case, but it’s pretty cool: An assessment of algorithms to estimate respiratory rate from the electrocardiogram and photoplethysmogram - PMC

Thanks this is helpful, I’ll make a custom work out that ramps up every 10 min from 60% heart rate and see if I can see what happens to the respiratory rate graph on Garmin Connect. Seiler said a good indicator of going too hard at endurance, is when your heart rate increases over time, despite being well hydrated and not over heating