In this blog I’d like to try to address a common concern, i.e. having a relatively low HRV in absolute terms. It is only normal to get worried considering the amount of misinformation out there, and our poor understanding of what different values might mean.
Thank you for the article. I am 66 now and until 2 years back, I was not active about my health. I bought a fitbit and started walking half an hour every day. I discovered that the fitbit is not very accurate if you move briskly, I had peaks of up to 160 heartbeats during walks. I didn't trust it and bought a polar h10 strap. It gave reliable results: the fitbit was not reliable. I wanted to know my progress better and found HRV4training, among others. To my shock, my HRV turned out to be between 6 and 7. But slowly, between the lines, I could read that I shouldn't infer too much about the condition of my heart from that. I welcome this article and happily continue my walks.
Thanks great explaining as always!
When are you adding the 60 to 70 year old range? I am in that range. It would be helpful. Thanks
If HRV is individual, why do you show the population comparison chart in the app? It's irrelevant according to your article. Good article by the way. I have HRV on the lower end and have worried about getting it up. I heard conflicting things from my readings, but I trust your research.
I've been using HRV4Training for a long time, and HRV4Biofeedback for about 6 months (the data aspect of it makes me do deep breathing to calm stress whereas I find it impossible to do meditation consistently). I have noticed that my HRV will often dip after a rest day, probably because I find it psychologically important to exercise and thus tend to adjust exercise intensity rather than rest altogether. I am particularly interested in the overlaps between HRV and stress. When I started monitoring HRV mine was lower than I would have expected given my age and fitness, but knowing there is a link with stress has helped me join a lot of dots.
And to add to this post - certain cardiac procedures like ablation for arrhythmias do result (sometimes) in vagal denervation. In some cases this goes away in some months but in some - it persists for years. Heart and hearth rhythm are Ok but it’s just that hrv is no longer a viable metric because the heart no longer has the “sensitivity” for vagal tone changes. For reference- my rmssd varies from 5 to 8 based on Oura ring, a year after ablation for PVCs.
Thanks Marco! Very insightful. I'm one of those people with relatively low rMSSD. Interestingly, last week I had a bit of a flu with runny and congested nose and my HRV was about 30-40% higher, shouldn't it be the opposite? Could it be that because of it I didn't have training stressors?
Glad someone is paying close attention to HRV.
For me, the greatest source of variation is _when_ measurements are taken. My Apple watch randomly measures HRV throughout the day and night. Some days the measurements can vary from 5 to 200 (I am healthy and middle-aged). I've found that I can get consistent readings using the built-in Breathe app for 2 minutes, but only if the following conditions are met:
1. I've been sitting for at least 5 minutes,
2. Have not exercised in the last 2 hours or so (depending on the intensity)
3. Have been awake for at least an hour.
After deleting all of the random measurements and only keeping "good" measurements, I have very consistent day to day trends.
The most interesting thing is the natural variations that are independent of stressors. I would love to understand exactly what hormones are keeping my HRV within a fairly narrow band (under optimal stress levels and measurement consistency). My long term average is 65, but it slowly goes up and down over 3-8 days between about 60-70, again assuming no illness or unusual stress, and also assuming a light exercise routine (walks and slow jogging). When I do weight training or a run it will go down to around 55 for about a day, and work stress and illness will do the same. On my worst day of covid it went down to 40.
The important thing is that the random measurements of my Apple watch are almost useless because a single very low or high measurement (typically while I'm asleep) completely skews the averages, making day-to-day trending impossible. But that is easily fixed by keeping only controlled measurements, and deleting the random measurements. Note, prior to adopting the habit of deleting the random measurements, my long term average was about 40.
Hey Marco! Thank you. I was curious to know a bit more on the opposite: what does it mean to have a continuous high(er) HRV? Aspects of a low HRV are often highlighted whereas the meaning of a high HRV remains unclear to me. Thank you! Great fan!!!