Using Heart rate monitoring to help with pacing.

My watch has this monitoring one that is for stress. At first I thought it was some ridiculously useless setting as it endlessly congratulates me on restful periods. But I have learned to ignore that bit and realized it shows me what causes me exertion to an extent. I think this is based on if your heart rate matches your activity level.

Anyhow, helps me pinpoint, looking back, what activities had more likely positive and negative effects (and when medication starts wearing off).
 

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That is what individual members have stated - that there is a considerable unpredictability. Moreover, it seems that major 'crashes' are pretty had to predict.
The unpredictability comes mostly from inability to measure/estimate the exertion across different activities. If you take just one exercise, walking for example, you can more reliably trigger, or avoid, PEM by walking certain distance/speed. That is the reason why patients employ fixed routine as a way to avoid PEM.
 
The unpredictability comes mostly from inability to measure/estimate the exertion across different activities.

Not from what I have heard. People talk of crashes coming out of the blue. And even when there seems to be a trigger it is always hard to know that it has not been attributed simply because we do that automatically. Everyone wants to have something to blame. If it is hard to measure exertion then we aren't in a position to know anyway.
 
I can’t go from my daybed to the bathroom (4 meters), then to the fridge (9 meters) and then to the bed (10 meters, 23 in total) without getting pain and a flu-like feeling for up to a day, with a delay of onset of just up to an hour. But I do any of the shorter trips multiple times a day.
Again, it seems that something is doing very precise accounting but inappropriately, which is interesting. Presumably the gut feeling of how much you have done doesn't;'t use the same memory stores in this case.
Adding to the anecdotes here: stomach issued had me make 5 trips to the bathroom (20m total) in about one hour. No additional pain or unexpected symptoms yet.

The time spent upright was also longer than what it usually is for that amount of distance covered.

I’m contemplating doing a 25m continuous walk next week, but it’s probably a bad idea.
 
That is what individual members have stated - that there is a considerable unpredictability. Moreover, it seems that major 'crashes' are pretty had to predict.
I think rolling PEM is an issue , particularly for new / mildly affected .

PEM can be caused also by a build up , not provoked by a single incident . This makes it particularly difficult to unravel . It makes it so insidious

HRM and apps may have a role here, as you have data over time which can be interrogated and linked to activity / life events


Emotional PEM is the hardest to guage for us.
 
Not from what I have heard. People talk of crashes coming out of the blue.
Some may. But most would agree that there is a strong relationship between exertion and crash most of the time. (There are triggers other than exertion that could trigger PEM seemingly out of the blue, but that does not mean exertion above certain level is a cause). The question here is whether the exertion threshold for the trigger exist. There is a way to test it if that is in doubt: remove other possible triggers best you can, let the patient rest for 3 days, and then have the patient walk certain distance at certain speed. If you can trigger PEM at or above certain distance/speed most of time, then we could conclude that exertional threshold exists. (Again, an observational study with actimeters could substitute). I think it is important that we establish that if you have any doubt about it. It's going to go a long way to accept/reject candidate hypotheses.

If it is hard to measure exertion then we aren't in a position to know anyway.
Actually, (total) exertion itself is rather easy to measure. You can define it as the rate of energy expenditure, or power/MET. It is the damage pertinent to PEM that is hard to measure. Smaller exertion of muscles that haven't been used for a while may trigger PEM while larger exertion of the walking muscles may not, for example. You need take into account the condition the patient is in at the time of exertion if you want to be precise. But establishing a general correlation between exertion and PEM probably is enough. That it is hard does not mean that it is irrelevant. though. That is why I'm working on it!
 
Not from what I have heard. People talk of crashes coming out of the blue.
One thing I forgot to mention: patients in mild/recovered stage are less likely talk of crashes coming out of the blue. Other triggers and accumulation effect are minimal in that stage and therefore the effect of exertion is much more pronounced. This is why I keep saying that the research should consider the entire spectrum rather than focusing on severe/moderate side only.
 
One thing I forgot to mention: patients in mild/recovered stage are less likely talk of crashes coming out of the blue. Other triggers and accumulation effect are minimal in that stage and therefore the effect of exertion is much more pronounced. This is why I keep saying that the research should consider the entire spectrum rather than focusing on severe/moderate side only.
This is true of my experience. When I was mild and still working it was very clear what my triggers were even with delayed responses.

Currently moderate and it feels like a mix. I have triggers like before but also others I can't always figure out.
 
If you can trigger PEM at or above certain distance/speed most of time, then we could conclude that exertional threshold exists. (Again, an observational study with actimeters could substitute). I think it is important that we establish that if you have any doubt about it. It's going to go a long way to accept/reject candidate hypotheses.

I realise that I have been recommending this was done for over 5 years now (recalling a particular event that has a date). As you say, it makes all the difference to viability of hypotheses.
Actually, (total) exertion itself is rather easy to measure. You can define it as the rate of energy expenditure, or power/MET.

I am not sure that is even agreed. Exertion might be force, power or total energy consumption. Members talk as if they think it is the total energy consumption that matters, not the force or power output per se. And yes, changes in muscle that might trigger a delayed reaction may depend on previous use and also the type of use. It is well established that contracting a muscle while it is lengthening (as you do going down stairs) does more damage than contacting one while it is shortening, at least during training.
 
One thing I forgot to mention: patients in mild/recovered stage are less likely talk of crashes coming out of the blue. Other triggers and accumulation effect are minimal in that stage and therefore the effect of exertion is much more pronounced. This is why I keep saying that the research should consider the entire spectrum rather than focusing on severe/moderate side only.
Same for my experience. From my perspective, having gone from homebound to mild, it is much easier to conceive of it being much harder to gauge the effect of cumulative exertion and other modulating factors when more severe, rather than positing that milder pwME are inaccurately assigning a cause to their PEM.

I actually hadn’t heard of ME/CFS or PEM for several months when I became ill, and yet from symptom tracking I could discern a pattern quite easily over time. I was actually quite primed to believe it was stress-induced from all my doctors at that time. I highly doubt that my ability to clearly see a pattern here is some kind of confirmation bias from needing to find a pattern in the madness.
 
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And while I’ll concede that anyone is prone to confirmation bias, it really does tend to be a clear and obvious relationship at the milder end of the spectrum. Early on in my illness I even asked some disabled friends to analyze my symptom journal for me just to see if they came to the same conclusions with different starting assumptions.

I hope others understand why I might not take kindly to the suggestion that I don’t know what’s really causing my PEM when I’ve already spent years unnecessarily doubting my ability to make those (proven to be robust, over time) conclusions due to constant gaslighting.

[Edit: perhaps the feasibility and reliability of gauging one’s own exertion is something that only becomes obvious when living with the illness]
 
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If you can trigger PEM at or above certain distance/speed most of time, then we could conclude that exertional threshold exists

Exertional thresholds definitely exist, but it is task specific. I can't predict it at all from heart rate alone. But only heart rate while doing a specific task in a very specific way.

How would heart activity play a role if beta blockers seem to have no worthwhile effect?

It has nothing to do with the heart rate itself, but the specific nature of the use of the muscles in my experience.


Does it have to be some part of the brain keeping score of exertion?

There is zero evidence, or even theoretical basis for the brain "keeping score" of exertion in a predictive way. It is just responding to the signals it is given (which help modulate activity, appropriate cardiovascular responses to further exertion etc). Those signals can be blocked in humans so we know it is not a memory/predictive based system.

There is no evidence that the hypothalamus does any sort of predictive energy accounting as JE suggests.
 
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Not from what I have heard. People talk of crashes coming out of the blue. And even when there seems to be a trigger it is always hard to know that it has not been attributed simply because we do that automatically. Everyone wants to have something to blame. If it is hard to measure exertion then we aren't in a position to know anyway.
Yes, some crashes come out of the blue, but that does not mean all crashes are totally unpredictable. Most of us know from experience that some specific exertions or stimuli, and the cumulative effect of combining some types and duration of activities, will always trigger a crash. That's the whole point of pacing - to reduce the frequency and severity of the predictable crashes when possible. We also hope it will reduce the likelihood of the unpredictable ones.
 
There is zero evidence, or even theoretical basis for the brain "keeping score" of exertion in a predictive way. It is just responding to the signals it is given (which help modulate activity, appropriate cardiovascular responses to further exertion etc). Those signals can be blocked in humans so we know it is not a memory/predictive based system.

There is no evidence that the hypothalamus does any sort of predictive energy accounting as JE suggests.
If you block the signals to/from the brain, how can you know that the brain isn’t keeping track in some way just because you don’t get the same results?
 
Actually, (total) exertion itself is rather easy to measure. You can define it as the rate of energy expenditure, or power/MET.

I don't know. I can hoover, shower and prepare a simple meal and I'm definitely out of breath after hoovering - all without triggering PEM. However, walking to the neighbours to collect a parcel (maybe 50m return) triggers PEM regardless of heart rate and how slowly I walk.

I wear a heart rate monitor, but I no longer check it and just go about my day as heart rate doesn't seem to be a reliable indicator of PEM for me.
 
There is zero evidence, or even theoretical basis for the brain "keeping score" of exertion in a predictive way.

Yes there is. I go for a walk most days and when I get back I usually guesstimate how many steps I have done. I am usually reasonably accurate. However it does it, the brain keeps score. Events keep score of how far they have walked in any given direction.
 
Yes there is. I go for a walk most days and when I get back I usually guesstimate how many steps I have done. I am usually reasonably accurate. However it does it, the brain keeps score. Events keep score of how far they have walked in any given direction.
Or, the more parsimonious explanation would be that this activity has a pretty consistent impact on metabolic state, which is what the brain is actually sensing.

In other threads you've also brought up the example of the brain "keeping track" of what you've eaten throughout the week. I'd argue the more parsimonious explanation there is that it is simply able to detect signals related to stores of specific macronutrients.

Some learning may be involved to associate those macronutrients with particular food. But in both cases, it is unnecessary to posit an unsubstantiated neural accountant "keeping track" of everything when we already know many ways that the brain senses exertion, or nutrient supply, peripherally.
 
If you block the signals to/from the brain, how can you know that the brain isn’t keeping track in some way just because you don’t get the same results?
The brain is of course involved in received and integrating those signals, but the point @Snow Leopard is making is that any "accounting" the brain does is primarily a matter of sorting out sensory input. If it was solely a predictive model in the brain, you should be able to get accurate results regardless of whether or not the brain has access to that sensory input from metabolic-sensing afferents. Which is not what we see.
 
Oooo I need to look up parsimonious, never heard that word before.
I must admit I probably use it a bit too often, but it's just so fun to say!

I decided to look it up again to find out the etymology--apparently it's related to frugality, which makes sense! In the case of logical arguments, it has an "Occam's Razor" meaning. i.e. the best explanation is the one that fits all the evidence in the least complicated way, without unnecessary frills or unsubstantiated leaps.
 
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