Nicely coincidental timing as this is the kind of data I am seeing now for the last 4 days in an upwards trend but I feel more than fine so I suspect I have crossed some sort of fitness threshold with increased careful training and this is the new normal, I will report back because I am as curious as anyone as to whether this reflects something good or bad. Keep up the great work, scientific content and analyses mixed with real life work for me
Very interesting subject, as last week I had arthroscopic surgery for a ski accident that resulted in torn medial and lateral meniscus and to repair a chondral defect (multiple). I did not take any narcotics for pain, just acetaminophen and ibuprofen. My all night RHR dropped 4 bpm, and my HRV was very high. confused me as I am "naive" in that generally I believe a higher HRV (within range) is better. Thanks for the perspective.
Have you noticed any correlations with calorie deficit? I've noticed when I finish my last meal at lunch or am in a calorie deficit my overnight HRV goes up substantially and I had a very high morning measurement today too.
yes, same, but in my case I see it even more in resting heart rate, which has always a clear suppression when in deficit (while HRV might be elevated, but at times isn’t)
This is so interesting. I have had a consistent RHR in the “normal” threshold mid-50s-mid-60s and a lower HRV based on age range (40-70, give or take sleep and harder training) for the last two years (when I started tracking such measures). I had a cardiac ablation in February and my RHR has been low 40s and HRV very high +200 for the last 4 months. I am an avid runner but have been approaching my training very conservatively. Overall I am feeling pretty good but tire more easily. I would love to see more data on this or something more in the literature.
Hey Marco I’ve been wearing a Whoop for about 6 months and noticed my HRV is much higher then what anyone ever mentions. My range while sleeping is between 130-180 generally. When I’m awake my Apple Watch is usually 60-90. I’m 35 male. Train but in no means an athlete. Looked back at my Apple Watch data from 2021 and it’s always been this way. Curious if you ever met anyone with these numbers and what to make of it? Everyone I ask is always confused. I did an ekg back in 2020 and everything was fine. Also never had any heart alerts on Apple Watch.
hello Eric, the numbers are within what is common in the population, maybe higher than most people, but still fairly common in my experience (and in published data). In case of concerns, of course the best thing to do is always to have a cardiologist look at your ECG, which sounds like you did already. All the best!
Ok that is good to hear. Appreciate the reply. I was reading one of your other articles and a tweet you referenced mentionned sleep apnea could affect your HRV. Would sleep apnea be a condition that lowers HRV or increases it?
thanks Eric, it would be reduced, but wearables might provide inaccurate data due to different types of artifacts in these cases, hence I would not necessarily trust the data
This post really hit home for me. I'm on a journey I call Not a Superhero, where I focus on improving my health and fitness through cycling, inspired by losing my father to heart issues.
Your insights on HRV and how "higher isn’t always better" really resonated. I’ve noticed spikes in my HRV after tough rides and wasn't sure what to make of them. Your explanation that these might indicate my body is "busy recovering" rather than ready to go hard again makes a lot of sense.
I still have a hard time listening to my body and often don't understand its signals. I tend to be nervous and overly anxious, suspecting the worst. Do you have any advice on how to learn to better interpret these signals?
Thanks for sharing your knowledge in such an accessible way!
thanks a lot Björn, much appreciated. As per the physiology, I think in many cases we just do not know and need to be honest about it. That's why I also wrote this blog post, it is naive and incorrect to think that higher is always better, but at the same time, we might not fully understand what some of these deviations from our normal might represent. What I try to do normally is simply to take note and see how they relate to my subjective feel, over time, and over repeated events, to see if there is some pattern in there. If I consistently feel good despite a physiological change, and then physiology re-normalizes in the short term (e.g. a day or two), then maybe it is not something I should over-interpret. If instead I do not feel good, then maybe it is a signal that I can make some adjustment (in training or else). Eventually both parts (objective and subjective) are important.
Thanks so much for your reply. I really appreciate your honesty about the uncertainties in physiology. It’s comforting to know that even the experts are still figuring things out!
Your approach to taking note of deviations and seeing how they relate to subjective feelings over time is really insightful. It’s a reminder that while data is valuable, our own experiences and feelings are just as important. I’ve been trying to find that balance myself – not over-interpreting every fluctuation but staying mindful of how I actually feel.
I use WHOOP to track my metrics, and it definitely helps me oversee the values and changes. Maybe I'll try and start noting patterns more consciously, just like you suggested. It’s reassuring to think that if physiological changes re-normalize quickly and I’m feeling good, it might not be something to stress over. And if not, it’s a sign to make some adjustments. This balanced perspective between objective data and subjective experience is something I’ll carry forward in my journey.
Thanks again for sharing your wisdom and for the thoughtful response.
I’m currently with flu like symptoms, going to the doctor today. But even though I feel tired and sick my HRV is higher than baseline (11% higher) and my RHR is at an all time low (46bpm, baseline is 50-52bpm, my fitness has improved in the last 6 months with better overall habits and my baseline changed from 60-62 to 50-52 also my HRV from 52 to 73ms) and my WHOOP interprets that as a high recovery and on top of that I had poor sleep performance last night (59%), also I haven’t worked out since Friday and have had a restorative weekend (7.2 and 9.2 strain). This note helped a lot since I was asking my whoop coach (an AI) about this and didn’t had information to share about it. I’m going to update on the doctors appointment and my metrics in the next days since this can help more people.
thanks a lot Diego, I appreciate this comment and feedback. Lots of marketing behind certain tools, but the way the data is used is really basic and often incorrect. Keep an eye for outliers, and aim for stability, more than 'higher is better' (https://marcoaltini.substack.com/p/stability-in-heart-rate-variability). Get well soon!
Thanks. I already read your other blog mentioned in this one and purchased HRV4Training app, took my first measurement today. Tried both the camera and using my WHOOP option. What of the two do you think I should stick with?
thank you Diego, I appreciate the support as well. Regarding the method: up to you, if you plan to keep using the wearable then you can also use it for a morning measurement with our app, otherwise the camera is what I use for simplicity. I would recommend to stick to one method though: while they are comparable and often equivalent, there can be small differences (even just based on the location of the measurement) and therefore it is preferable to use the same method consistently over time.
That’s for the post. I searched for your thoughts on this topic today because my resting HRV today was abnormally high at 8.9 with a baseline of 7.7 and a range of 6.9-7.8. My resting HR was typical, although trending downward slightly at 57 with a range of 56-61.
I’m 10 days or so from a peak performance 2km rowing event but have been slightly tired. I have been resting since the performance.
I saw no acute physical or mental reason why I have the high resting HRV today. The only potential explanation I can think of is related to the menstrual cycle. I’m 52 and am in the perimenopause zone. Just curious if you have any data related to perimenopause and HRV. If not, feel free to add my anecdotal evidence :-)
thanks Jess! I would think there are changes at least to be experienced chronically with perimenopause as resting physiology in some way also tracks hormonal changes. Possibly also acutely as you are experiencing, I appreciate your input and feedback!
As someone who's super into medicine & data, I really love this article -- you strike a nice balance between looking at numbers & analyzing subjective feelings or context. I found this article because my Fitbit bugged me about a sudden increase in my HRV last night... Which makes sense, as I started strength training yesterday evening after a long hiatus! My RHR is still looking good, so my body just needs a solid rest to keep performing. I like your style, so now I'm gonna start reading the rest of your content!! :)
Thanks for this post. I've been increasing my training volume with easy riding/running for a couple days. On the third day I did a tempo session and noticed my DFA a1 was heavily suppressed for a given power/HR so didn't push too much in the session - I woke up with an HRV 24% above average but resting HR was fine so was wondering how to interpret that. Rest day it is!
thanks! not always easy in these cases as sometimes "higher is fine", but indeed it seems that quite often we can see higher values as abnormalities, and we should be more cautious (depending on how we feel, probably). All the best!
I am an endocrinology and metabolism specialist from Turkey. I have written books on Metabolic Fitness.
Every place and every organ in our body wants to be in good balance. This is the job of the autonomic nervous system. The organ that misses this balance becomes sick in a long time. In those with prominent insula functions in the brain, there is already parasympathetic system dominance. This is manifested by a tendency towards HRV elevation. When people with this metabolic balance experience an event or situation that will increase HRV, the rate of parasympathetic sympathetic system activation increases in favor of the parasympathetic. When HRV is high, the pulse is low. This can be detected in advanced measurement devices by measuring the ratio of high frequency and low frequency heart rate variability. However, in devices such as personal measurement rings, etc., this direction can be viewed and users can be informed with the heart rate and HRV rate tracking algorithm.
1. At 03 at night, 2. Before getting up in the morning
I don't think this is a thing (i.e. inducing a higher HRV, with stress, it is the opposite, and when it does happen, typically it is either measurement error via an arrhytmia or a negative response, highlighting that rest is required). Only very minimal changes have been seen systematically, wrt to measurements prior to a workout session. I wonder also if things were just not measured properly in the older days, i.e. now we would compare to a person's normal range, and I would expect the higher performers to have their HRV within the normal range quickly, while it would take more time to e.g. non-elite athletes. This wasn't really done in the earlier days when there was no daily measurement at home and no concept of a normal range to use for individual comparison. Just some thoughts, happy to change my mind if the evidence changes!
Hi I had suddenly a very high hrv and my Apple Watch signaled cardiac arrhythmias. Turned out ending in hospital with atrial fibrillation. I was helped by a cardioversion (if that’s the right translation) If I didn’t have the Apple Watch I would be alerted by the high hrv….
I am alright now. Can continue training with no restrictions.
Interesting. I do not have any device that can calculate my hrv. But I have Polar Ingite 2. I used to download my data from polar and there are ppi files available. I am applying rmssd formula there and getting hrv at night from 20 to 50 and at day up to 250 sometimes. Am I already dead?
hi Damon, this sounds like a possible artifact in the night (the casue could be the sensor or actual ectopic beats), I would maybe double check with an ECG (if you refer to the average being that high, it is otherwise normal to have more oscillations during the night, even though given the baseline you mention, this still sounds like an artifact or a noisy data point in case you are not referring to an average)
Nicely coincidental timing as this is the kind of data I am seeing now for the last 4 days in an upwards trend but I feel more than fine so I suspect I have crossed some sort of fitness threshold with increased careful training and this is the new normal, I will report back because I am as curious as anyone as to whether this reflects something good or bad. Keep up the great work, scientific content and analyses mixed with real life work for me
Very interesting subject, as last week I had arthroscopic surgery for a ski accident that resulted in torn medial and lateral meniscus and to repair a chondral defect (multiple). I did not take any narcotics for pain, just acetaminophen and ibuprofen. My all night RHR dropped 4 bpm, and my HRV was very high. confused me as I am "naive" in that generally I believe a higher HRV (within range) is better. Thanks for the perspective.
thank you Dean, your experience seems very similar to Gene's. Wishing you a prompt recovery
Have you noticed any correlations with calorie deficit? I've noticed when I finish my last meal at lunch or am in a calorie deficit my overnight HRV goes up substantially and I had a very high morning measurement today too.
yes, same, but in my case I see it even more in resting heart rate, which has always a clear suppression when in deficit (while HRV might be elevated, but at times isn’t)
This is so interesting. I have had a consistent RHR in the “normal” threshold mid-50s-mid-60s and a lower HRV based on age range (40-70, give or take sleep and harder training) for the last two years (when I started tracking such measures). I had a cardiac ablation in February and my RHR has been low 40s and HRV very high +200 for the last 4 months. I am an avid runner but have been approaching my training very conservatively. Overall I am feeling pretty good but tire more easily. I would love to see more data on this or something more in the literature.
Hey Marco I’ve been wearing a Whoop for about 6 months and noticed my HRV is much higher then what anyone ever mentions. My range while sleeping is between 130-180 generally. When I’m awake my Apple Watch is usually 60-90. I’m 35 male. Train but in no means an athlete. Looked back at my Apple Watch data from 2021 and it’s always been this way. Curious if you ever met anyone with these numbers and what to make of it? Everyone I ask is always confused. I did an ekg back in 2020 and everything was fine. Also never had any heart alerts on Apple Watch.
hello Eric, the numbers are within what is common in the population, maybe higher than most people, but still fairly common in my experience (and in published data). In case of concerns, of course the best thing to do is always to have a cardiologist look at your ECG, which sounds like you did already. All the best!
Ok that is good to hear. Appreciate the reply. I was reading one of your other articles and a tweet you referenced mentionned sleep apnea could affect your HRV. Would sleep apnea be a condition that lowers HRV or increases it?
thanks Eric, it would be reduced, but wearables might provide inaccurate data due to different types of artifacts in these cases, hence I would not necessarily trust the data
This post really hit home for me. I'm on a journey I call Not a Superhero, where I focus on improving my health and fitness through cycling, inspired by losing my father to heart issues.
Your insights on HRV and how "higher isn’t always better" really resonated. I’ve noticed spikes in my HRV after tough rides and wasn't sure what to make of them. Your explanation that these might indicate my body is "busy recovering" rather than ready to go hard again makes a lot of sense.
I still have a hard time listening to my body and often don't understand its signals. I tend to be nervous and overly anxious, suspecting the worst. Do you have any advice on how to learn to better interpret these signals?
Thanks for sharing your knowledge in such an accessible way!
Cheers,
Björn
thanks a lot Björn, much appreciated. As per the physiology, I think in many cases we just do not know and need to be honest about it. That's why I also wrote this blog post, it is naive and incorrect to think that higher is always better, but at the same time, we might not fully understand what some of these deviations from our normal might represent. What I try to do normally is simply to take note and see how they relate to my subjective feel, over time, and over repeated events, to see if there is some pattern in there. If I consistently feel good despite a physiological change, and then physiology re-normalizes in the short term (e.g. a day or two), then maybe it is not something I should over-interpret. If instead I do not feel good, then maybe it is a signal that I can make some adjustment (in training or else). Eventually both parts (objective and subjective) are important.
Thanks so much for your reply. I really appreciate your honesty about the uncertainties in physiology. It’s comforting to know that even the experts are still figuring things out!
Your approach to taking note of deviations and seeing how they relate to subjective feelings over time is really insightful. It’s a reminder that while data is valuable, our own experiences and feelings are just as important. I’ve been trying to find that balance myself – not over-interpreting every fluctuation but staying mindful of how I actually feel.
I use WHOOP to track my metrics, and it definitely helps me oversee the values and changes. Maybe I'll try and start noting patterns more consciously, just like you suggested. It’s reassuring to think that if physiological changes re-normalize quickly and I’m feeling good, it might not be something to stress over. And if not, it’s a sign to make some adjustments. This balanced perspective between objective data and subjective experience is something I’ll carry forward in my journey.
Thanks again for sharing your wisdom and for the thoughtful response.
I’m currently with flu like symptoms, going to the doctor today. But even though I feel tired and sick my HRV is higher than baseline (11% higher) and my RHR is at an all time low (46bpm, baseline is 50-52bpm, my fitness has improved in the last 6 months with better overall habits and my baseline changed from 60-62 to 50-52 also my HRV from 52 to 73ms) and my WHOOP interprets that as a high recovery and on top of that I had poor sleep performance last night (59%), also I haven’t worked out since Friday and have had a restorative weekend (7.2 and 9.2 strain). This note helped a lot since I was asking my whoop coach (an AI) about this and didn’t had information to share about it. I’m going to update on the doctors appointment and my metrics in the next days since this can help more people.
thanks a lot Diego, I appreciate this comment and feedback. Lots of marketing behind certain tools, but the way the data is used is really basic and often incorrect. Keep an eye for outliers, and aim for stability, more than 'higher is better' (https://marcoaltini.substack.com/p/stability-in-heart-rate-variability). Get well soon!
Thanks. I already read your other blog mentioned in this one and purchased HRV4Training app, took my first measurement today. Tried both the camera and using my WHOOP option. What of the two do you think I should stick with?
Both displayed the same results
thank you Diego, I appreciate the support as well. Regarding the method: up to you, if you plan to keep using the wearable then you can also use it for a morning measurement with our app, otherwise the camera is what I use for simplicity. I would recommend to stick to one method though: while they are comparable and often equivalent, there can be small differences (even just based on the location of the measurement) and therefore it is preferable to use the same method consistently over time.
That’s for the post. I searched for your thoughts on this topic today because my resting HRV today was abnormally high at 8.9 with a baseline of 7.7 and a range of 6.9-7.8. My resting HR was typical, although trending downward slightly at 57 with a range of 56-61.
I’m 10 days or so from a peak performance 2km rowing event but have been slightly tired. I have been resting since the performance.
I saw no acute physical or mental reason why I have the high resting HRV today. The only potential explanation I can think of is related to the menstrual cycle. I’m 52 and am in the perimenopause zone. Just curious if you have any data related to perimenopause and HRV. If not, feel free to add my anecdotal evidence :-)
thanks Jess! I would think there are changes at least to be experienced chronically with perimenopause as resting physiology in some way also tracks hormonal changes. Possibly also acutely as you are experiencing, I appreciate your input and feedback!
As someone who's super into medicine & data, I really love this article -- you strike a nice balance between looking at numbers & analyzing subjective feelings or context. I found this article because my Fitbit bugged me about a sudden increase in my HRV last night... Which makes sense, as I started strength training yesterday evening after a long hiatus! My RHR is still looking good, so my body just needs a solid rest to keep performing. I like your style, so now I'm gonna start reading the rest of your content!! :)
thanks!
Thanks for this post. I've been increasing my training volume with easy riding/running for a couple days. On the third day I did a tempo session and noticed my DFA a1 was heavily suppressed for a given power/HR so didn't push too much in the session - I woke up with an HRV 24% above average but resting HR was fine so was wondering how to interpret that. Rest day it is!
thanks! not always easy in these cases as sometimes "higher is fine", but indeed it seems that quite often we can see higher values as abnormalities, and we should be more cautious (depending on how we feel, probably). All the best!
Hello,
I am an endocrinology and metabolism specialist from Turkey. I have written books on Metabolic Fitness.
Every place and every organ in our body wants to be in good balance. This is the job of the autonomic nervous system. The organ that misses this balance becomes sick in a long time. In those with prominent insula functions in the brain, there is already parasympathetic system dominance. This is manifested by a tendency towards HRV elevation. When people with this metabolic balance experience an event or situation that will increase HRV, the rate of parasympathetic sympathetic system activation increases in favor of the parasympathetic. When HRV is high, the pulse is low. This can be detected in advanced measurement devices by measuring the ratio of high frequency and low frequency heart rate variability. However, in devices such as personal measurement rings, etc., this direction can be viewed and users can be informed with the heart rate and HRV rate tracking algorithm.
1. At 03 at night, 2. Before getting up in the morning
3. Within the day
Good luck
I wonder what you think about a training plan that produces a higher than normal HRV to enter "parasympathetic dominance" as an indicator of accelerated recovery as described in this article . Provided it is asymptomatic I would presume, rather than feeling more tired than usual. https://8weeksout.com/2017/11/29/train-recover-faster-ever-new-science-high-performance-recovery-training/
I don't think this is a thing (i.e. inducing a higher HRV, with stress, it is the opposite, and when it does happen, typically it is either measurement error via an arrhytmia or a negative response, highlighting that rest is required). Only very minimal changes have been seen systematically, wrt to measurements prior to a workout session. I wonder also if things were just not measured properly in the older days, i.e. now we would compare to a person's normal range, and I would expect the higher performers to have their HRV within the normal range quickly, while it would take more time to e.g. non-elite athletes. This wasn't really done in the earlier days when there was no daily measurement at home and no concept of a normal range to use for individual comparison. Just some thoughts, happy to change my mind if the evidence changes!
Hi I had suddenly a very high hrv and my Apple Watch signaled cardiac arrhythmias. Turned out ending in hospital with atrial fibrillation. I was helped by a cardioversion (if that’s the right translation) If I didn’t have the Apple Watch I would be alerted by the high hrv….
I am alright now. Can continue training with no restrictions.
Greetings Gerard
Interesting. I do not have any device that can calculate my hrv. But I have Polar Ingite 2. I used to download my data from polar and there are ppi files available. I am applying rmssd formula there and getting hrv at night from 20 to 50 and at day up to 250 sometimes. Am I already dead?
But from time to time I am getting very weird readings from Polar. Like when I am on a threadmill and my hr == 180 polar can easily show 130 and lower
My HRV IS consistently between 95 and 116 according to whoop
My HRV is usually around a 40 or so, and working out it goes to 20. Just noticed yesterday that when I sleep, it goes to 180
hi Damon, this sounds like a possible artifact in the night (the casue could be the sensor or actual ectopic beats), I would maybe double check with an ECG (if you refer to the average being that high, it is otherwise normal to have more oscillations during the night, even though given the baseline you mention, this still sounds like an artifact or a noisy data point in case you are not referring to an average)