Question: considering you are in a caloric deficit I would suppose that also your last meal of the day is smaller and/or lighter. This improves sleep, lowers HR (the body is less active during the night for digestion) and thus improves recovery (leading probably to higher HRV).
Supposing you were not eating in a really bad way previously, is it possible that the variations you observed are related to the causes I mentioned before? The same observations for a person eating too much or not in a heathy way starting to eat less/better may be similar in quantity but not in quality.
ciao Martina! I think that the factor you mention can play a role, for example I often argue against using wearables / night data as they penalize you for e.g. eating a larger high carb dinner before a race, as your physiology during the night will be slightly altered (see here: https://marcoaltini.substack.com/p/eat-the-tortilla).
I do not think this applies as much for morning data though, as many hours have passed since the 'stressor' (dinner), and you've also had the restorative effect of sleep (a positive stressor) before the measurement, hence if I measure in the morning, there is a large change that is not closely linked to a previous acute stressor (such as food intake) but reflects my underlying physiology, and in particular in this case this 'energy conservation' strategy given the rapid weight loss.
In my specific case my dinners are pretty much the same (some lean protein + cooked vegetables) and most of the change comes from food eaten earlier (breakfast, snacks, etc.) hence the night data also reflects the change in underlying physiology more than 'dinner'. Or at least, these are my considerations at the moment.
Ciao Marco, thanks for the reply. Considering the detail about your dinner being almost the same it can play a role but minor, at least in your case. I was wandering if there could be a link between lighter dinner and better markers because I find that eating less (not too much in volume and easier foods to digest) improves a lot the quality of my sleep. My RHR is lower (around 40 with “heavy” evenings, around 35 when lighter and far from bed time). I feel more rested and HRV tends to stay higher even if I am doing an intermittent fasting where I fast 14hrs from evening to morning (last hours of the morning with the body probably starving for food).
As for many other things.. subjectiveness and we can never be sure about the real implications due to too much factors (known and unknown) XD
thank you Martina for sharing this, I think it's really interesting. Difficult to derive broad conclusions as there is much individuality. On my end, I try to be mindful not to necessarily associate a large change in resting physiology in the "good direction" as something positive, and try to see if there are other mechanisms at play, or if the body is truly more recovered. I don't have the answer, but it's something that we always need to keep in mind (especially with food intake which has a dramatic effect on resting physiology during both digestion and "starvation" - for lack of a better word, but this is also exemplified by anorexia, which is a chronic health condition but still comes with high HRV, hence high HRV might not be as simple as often advertised - that's my main message here). In your case it seems a positive association as you report also feeling better, hence it could be a useful indication in that regard. I hope this makes sense!
Thank you Marco, I learnt to verify data against feelings and not the opposite because - as you said - it's not that simple to have straight conclusions from a number that represents the result of a complex reality (complex and barely known in fact). HRV is usually for me a good linear indicator of my beeing-ok and many times - I must admit - it happened that I interpreted a negative trend was at first more like a bug ("there must be something wrong with data or something I'm doing is interfering..") and then in some days I realised that it was actually right. Other times a low value can be worrying but in fact it is just a signal of the body that is responding to a stressor (like in the first week of an altitude training). Not all stressors are sickness, in fact training is a process driven by stressors.. I was at first surprised reading in your reply that anorexia comes with high HRV but thinking a bit on that it makes sense.. anorexia is an extreme condition where food deprivation was just the start. Considering HRV as a signal of the body fighting to cope with something I can now better imagine why - when the body is so low in energies that fighting isn't a point any more but all functions are reduced to the minimum - why HRV is sadly high..
I find the same my HRV sky rockets and RHR decreases while dieting. I got my RHR to 41 at 103kg BW.
Something to add and would love your feedback on.
from 2020 to 2022 while my weight was under 100kg my average HRV was 134ms. This dropped to 93ms after weight gain. For 2023-2024. RHR2 bpm higher than 2020-2022.
So I see the increase in HRV while dieting as a good thing. Even tho I’m more tired.
thanks Angus! Glad your experience is consistent with this.
Regarding good/bad, I think the timescale matters. For example, acutely, a large change as we are seeing in the data I shared, is a signal that we need to be cautious (I believe), while chronically, over months-years, the change might also reflect better health. A bit like with training heart rate, an acute suppression tends to signal fatigue, but if our heart rate reduces over months or years, typically it's because of improved fitness (given a fixed workload).
Question: considering you are in a caloric deficit I would suppose that also your last meal of the day is smaller and/or lighter. This improves sleep, lowers HR (the body is less active during the night for digestion) and thus improves recovery (leading probably to higher HRV).
Supposing you were not eating in a really bad way previously, is it possible that the variations you observed are related to the causes I mentioned before? The same observations for a person eating too much or not in a heathy way starting to eat less/better may be similar in quantity but not in quality.
ciao Martina! I think that the factor you mention can play a role, for example I often argue against using wearables / night data as they penalize you for e.g. eating a larger high carb dinner before a race, as your physiology during the night will be slightly altered (see here: https://marcoaltini.substack.com/p/eat-the-tortilla).
I do not think this applies as much for morning data though, as many hours have passed since the 'stressor' (dinner), and you've also had the restorative effect of sleep (a positive stressor) before the measurement, hence if I measure in the morning, there is a large change that is not closely linked to a previous acute stressor (such as food intake) but reflects my underlying physiology, and in particular in this case this 'energy conservation' strategy given the rapid weight loss.
In my specific case my dinners are pretty much the same (some lean protein + cooked vegetables) and most of the change comes from food eaten earlier (breakfast, snacks, etc.) hence the night data also reflects the change in underlying physiology more than 'dinner'. Or at least, these are my considerations at the moment.
Ciao Marco, thanks for the reply. Considering the detail about your dinner being almost the same it can play a role but minor, at least in your case. I was wandering if there could be a link between lighter dinner and better markers because I find that eating less (not too much in volume and easier foods to digest) improves a lot the quality of my sleep. My RHR is lower (around 40 with “heavy” evenings, around 35 when lighter and far from bed time). I feel more rested and HRV tends to stay higher even if I am doing an intermittent fasting where I fast 14hrs from evening to morning (last hours of the morning with the body probably starving for food).
As for many other things.. subjectiveness and we can never be sure about the real implications due to too much factors (known and unknown) XD
Thanks for sharing.
thank you Martina for sharing this, I think it's really interesting. Difficult to derive broad conclusions as there is much individuality. On my end, I try to be mindful not to necessarily associate a large change in resting physiology in the "good direction" as something positive, and try to see if there are other mechanisms at play, or if the body is truly more recovered. I don't have the answer, but it's something that we always need to keep in mind (especially with food intake which has a dramatic effect on resting physiology during both digestion and "starvation" - for lack of a better word, but this is also exemplified by anorexia, which is a chronic health condition but still comes with high HRV, hence high HRV might not be as simple as often advertised - that's my main message here). In your case it seems a positive association as you report also feeling better, hence it could be a useful indication in that regard. I hope this makes sense!
Thank you Marco, I learnt to verify data against feelings and not the opposite because - as you said - it's not that simple to have straight conclusions from a number that represents the result of a complex reality (complex and barely known in fact). HRV is usually for me a good linear indicator of my beeing-ok and many times - I must admit - it happened that I interpreted a negative trend was at first more like a bug ("there must be something wrong with data or something I'm doing is interfering..") and then in some days I realised that it was actually right. Other times a low value can be worrying but in fact it is just a signal of the body that is responding to a stressor (like in the first week of an altitude training). Not all stressors are sickness, in fact training is a process driven by stressors.. I was at first surprised reading in your reply that anorexia comes with high HRV but thinking a bit on that it makes sense.. anorexia is an extreme condition where food deprivation was just the start. Considering HRV as a signal of the body fighting to cope with something I can now better imagine why - when the body is so low in energies that fighting isn't a point any more but all functions are reduced to the minimum - why HRV is sadly high..
That - for now - makes sense. XD
Thank you
Ciao!
Martina
I find the same my HRV sky rockets and RHR decreases while dieting. I got my RHR to 41 at 103kg BW.
Something to add and would love your feedback on.
from 2020 to 2022 while my weight was under 100kg my average HRV was 134ms. This dropped to 93ms after weight gain. For 2023-2024. RHR2 bpm higher than 2020-2022.
So I see the increase in HRV while dieting as a good thing. Even tho I’m more tired.
Many thanks
thanks Angus! Glad your experience is consistent with this.
Regarding good/bad, I think the timescale matters. For example, acutely, a large change as we are seeing in the data I shared, is a signal that we need to be cautious (I believe), while chronically, over months-years, the change might also reflect better health. A bit like with training heart rate, an acute suppression tends to signal fatigue, but if our heart rate reduces over months or years, typically it's because of improved fitness (given a fixed workload).