Thanks for posting this, I needed to hear this today. As a middle-aged medium-fit woman with some chronic diseases and menopause symptoms, I have worn a Garmin watch day and night for over a year now and it was hard to ignore the inaccurate assumptions it arrives at based on its generic estimates. It sucks to be shown a red or pink training status that says you are 'strained' or 'unproductive' for weeks, and for the HRV to be shown as 'low' or 'unbalanced' when you feel normal and your morning measurement shows it is just fine and you are good to go again. I try to stick to a sound training plan that builds muscle, incorprates 80/20 endurance traning and contains enough rest days for me individually so that I can keep going. Being told over and over again by my device that this is not so good for me and I should simultaneously add more high intensity training and rest more, is frustrating. I don't feel that these devices are for me. I'm clearly not the target group so I end up turning 'Training status' off a lot. Many women post in the forums, that they have problems with the estimations because they do not consider their hormonal cycle properly. That's like half the population that gets fed generic estimates that don't fit their bodies and training goals - and we cannot adjust the settings either. I'd love to be able to just adjust the settings. It would be a game changer.
Marco - interesting as always. I've been thinking about these issues a little bit recently. On a pure physiological basis I agree with you - much of physiology + model to infer some value seem to be mostly marketing/strong commitments to a very particular philosophy of science, both of which are equally present in academic research.
On the flip side I've been beginning to think that estimates and scores serve a useful psychological purpose. My hunch is that for many people (not elite athletes) these estimates/scores have enough accuracy, enough of the time, to be useful ways to create psychological meaning (essentially gamification) that helps one prioritize taking care of their body in a world full of noise.
The caveat to that view is that why not just use actual meaningful physiology (HRV measured sitting in the morning) to do this... to which my feeling is that scores/estimates maybe helpful we have a world full of noise and marketing :/
thanks Kieran, I understand what you are saying, and there was a time where I thought something similar (see here, where I did spend some good words on these scores, years ago: https://medium.com/@altini_marco/on-heart-rate-variability-hrv-and-readiness-394a499ed05b). However, at the moment, I do not think that we should treat people like 3 years old, intentionally fooling them with made up scores that really do not track readiness/recovery even outside of athletic contexts. For once, I have to support Apple's approach, which is in fact identical to hours, showing deviations from normal both in physiology and behavior, as a better approach with respect to making up things: https://x.com/altini_marco/status/1800408630057210174 - the reasons why I'm saying this now is that too many people have been derailed by these scores, or currently have developed unhealthy behaviors entirely because of wearables and their made up scores and gamification (the need for the scores to always change because you always have to do something, instead of simply reflecting that on most days, nothing really has changed, which would make for a boring but healthier tool): https://marcoaltini.substack.com/p/developing-healthier-relationships - this is taken to the extreme now with minute by minute stress scores (you are stressed, do a deep breathing exercise!), without any context, nor meaning: https://marcoaltini.substack.com/p/a-quick-note-on-continuous-heart - these are the features that drive the most engagement, sadly. To me, these things need to go. It would be a lot more helpful to anyone to wakeup and pause 10 seconds to assess subjectively how they feel, without any technology, then to use devices that pretend to understand things that they cannot possibly understand, based on inaccurate data poorly reflecting our behavior (sleep, activity, etc.). These devices are infuencing people's behavior and mental health in ways that is not increasing their awareness, but decreasing it, since there is very limited or no space for a conscious subjective assessment, while the device tells us what we should feel. As you can see my current thinking is not very positive :)
After posting the comment below I realized my point more clearly. It's that scores create psychological meaning in a relatively explicit way, but so does just measuring and tracking HRV. HRV it's self isn't intrinsically meaningful. It becomes physiologically meaningful based on the it's value relative to the person measuring it's baseline, given certain assumptions about how they're measuring it.
More over that physiological meaning needs to be converted into psychological meaning for people to act on it, this requires some amount of knowledge about the scientific literature surrounding HRV including it's limitations. I agree many companies seem to stray from inferences that are well supported by scientific data, and that the way one creates products to create meaning for people needs to be grounded, but I also think it's worth noting that we are constructing this.
For instance in HRV4Training there is some threshold at which point you cross from normal to suppressed, that threshold is chosen and I'm sure it's based on something scientifically realizable but at the same time a score just above or just below the threshold probably aren't meaningfully physiologically different. The app however creates additional psychological meaning by coloring one measurement yellow and the other blue. I think this is a good thing. Creating the extra psychological meaning allows us to function quickly and make decisions based on the data.
I think the question maybe more of what degree of extra meaning is reasonable and useful (HRV thresholding) vs maybe not useful and harmful (continuous stress score?), and here I completely defer to your experience and expertise :).
Hard to argue with any these points, and I love the unfiltered takes. I mostly completely agree and the comment above mine really speaks to this. Also to be fair one of the reasons I don't wear a wearable is I know the gamification will mess with my head in excess.
I think the deep breathing/continuous HRV is particularly good point as it's easy enough to change HRV with breathing rate which ends up being a very circular definition of stress (i.e. its impossible to be stressed if you're breathing slowly!).
I also completely agree that many of the fixes for these things may not necessarily be more technology - and I will fully retreat from my previous argument and agree that we can probably create the same sorts of psychological meaning with actually measured and physiologically meaningful signals.
Thanks for posting this, I needed to hear this today. As a middle-aged medium-fit woman with some chronic diseases and menopause symptoms, I have worn a Garmin watch day and night for over a year now and it was hard to ignore the inaccurate assumptions it arrives at based on its generic estimates. It sucks to be shown a red or pink training status that says you are 'strained' or 'unproductive' for weeks, and for the HRV to be shown as 'low' or 'unbalanced' when you feel normal and your morning measurement shows it is just fine and you are good to go again. I try to stick to a sound training plan that builds muscle, incorprates 80/20 endurance traning and contains enough rest days for me individually so that I can keep going. Being told over and over again by my device that this is not so good for me and I should simultaneously add more high intensity training and rest more, is frustrating. I don't feel that these devices are for me. I'm clearly not the target group so I end up turning 'Training status' off a lot. Many women post in the forums, that they have problems with the estimations because they do not consider their hormonal cycle properly. That's like half the population that gets fed generic estimates that don't fit their bodies and training goals - and we cannot adjust the settings either. I'd love to be able to just adjust the settings. It would be a game changer.
Marco - interesting as always. I've been thinking about these issues a little bit recently. On a pure physiological basis I agree with you - much of physiology + model to infer some value seem to be mostly marketing/strong commitments to a very particular philosophy of science, both of which are equally present in academic research.
On the flip side I've been beginning to think that estimates and scores serve a useful psychological purpose. My hunch is that for many people (not elite athletes) these estimates/scores have enough accuracy, enough of the time, to be useful ways to create psychological meaning (essentially gamification) that helps one prioritize taking care of their body in a world full of noise.
The caveat to that view is that why not just use actual meaningful physiology (HRV measured sitting in the morning) to do this... to which my feeling is that scores/estimates maybe helpful we have a world full of noise and marketing :/
thanks Kieran, I understand what you are saying, and there was a time where I thought something similar (see here, where I did spend some good words on these scores, years ago: https://medium.com/@altini_marco/on-heart-rate-variability-hrv-and-readiness-394a499ed05b). However, at the moment, I do not think that we should treat people like 3 years old, intentionally fooling them with made up scores that really do not track readiness/recovery even outside of athletic contexts. For once, I have to support Apple's approach, which is in fact identical to hours, showing deviations from normal both in physiology and behavior, as a better approach with respect to making up things: https://x.com/altini_marco/status/1800408630057210174 - the reasons why I'm saying this now is that too many people have been derailed by these scores, or currently have developed unhealthy behaviors entirely because of wearables and their made up scores and gamification (the need for the scores to always change because you always have to do something, instead of simply reflecting that on most days, nothing really has changed, which would make for a boring but healthier tool): https://marcoaltini.substack.com/p/developing-healthier-relationships - this is taken to the extreme now with minute by minute stress scores (you are stressed, do a deep breathing exercise!), without any context, nor meaning: https://marcoaltini.substack.com/p/a-quick-note-on-continuous-heart - these are the features that drive the most engagement, sadly. To me, these things need to go. It would be a lot more helpful to anyone to wakeup and pause 10 seconds to assess subjectively how they feel, without any technology, then to use devices that pretend to understand things that they cannot possibly understand, based on inaccurate data poorly reflecting our behavior (sleep, activity, etc.). These devices are infuencing people's behavior and mental health in ways that is not increasing their awareness, but decreasing it, since there is very limited or no space for a conscious subjective assessment, while the device tells us what we should feel. As you can see my current thinking is not very positive :)
After posting the comment below I realized my point more clearly. It's that scores create psychological meaning in a relatively explicit way, but so does just measuring and tracking HRV. HRV it's self isn't intrinsically meaningful. It becomes physiologically meaningful based on the it's value relative to the person measuring it's baseline, given certain assumptions about how they're measuring it.
More over that physiological meaning needs to be converted into psychological meaning for people to act on it, this requires some amount of knowledge about the scientific literature surrounding HRV including it's limitations. I agree many companies seem to stray from inferences that are well supported by scientific data, and that the way one creates products to create meaning for people needs to be grounded, but I also think it's worth noting that we are constructing this.
For instance in HRV4Training there is some threshold at which point you cross from normal to suppressed, that threshold is chosen and I'm sure it's based on something scientifically realizable but at the same time a score just above or just below the threshold probably aren't meaningfully physiologically different. The app however creates additional psychological meaning by coloring one measurement yellow and the other blue. I think this is a good thing. Creating the extra psychological meaning allows us to function quickly and make decisions based on the data.
I think the question maybe more of what degree of extra meaning is reasonable and useful (HRV thresholding) vs maybe not useful and harmful (continuous stress score?), and here I completely defer to your experience and expertise :).
Hard to argue with any these points, and I love the unfiltered takes. I mostly completely agree and the comment above mine really speaks to this. Also to be fair one of the reasons I don't wear a wearable is I know the gamification will mess with my head in excess.
I think the deep breathing/continuous HRV is particularly good point as it's easy enough to change HRV with breathing rate which ends up being a very circular definition of stress (i.e. its impossible to be stressed if you're breathing slowly!).
I also completely agree that many of the fixes for these things may not necessarily be more technology - and I will fully retreat from my previous argument and agree that we can probably create the same sorts of psychological meaning with actually measured and physiologically meaningful signals.