PEM discussion thread - post-exertional malaise
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So do you think the nervousness precipitated the PEM or did the nervousness create the insomnia and being awake for so long precipitated the PEM?
Not speaking for Kitty, but I also get insomnia the night after a day of intense overexertion. Might take like 3-4 hours longer to fall asleep. This is before any real PEM. It just feels kind of like trying to sleep after drinking a coffee.
I guess it's possible less or worse sleep can at least partly cause PEM.
If we were to say PEM is caused by energy being expended beyond a certain level then this would make sense.
Patients discuss limiting exertion but what they refer to is limiting exertion they control, most energy is used outside of our control to keep us functioning day-to day. Beyond that, it sounds like sometimes things happen to patients that are beyond their control and burn more energy. Being awake burns more energy than being a sleep, feeling wired or anxious burns more energy than feeling relaxed, etc.
I suspect PEM is often precipitated by burning energy beyond the patient control. If it is fight-flight then the autonomic measurements like HRV could be useful as a predictor of PEM.
Kitty
Senior Member (Voting Rights)
I don't think it was a big factor, but feeling a bit nervy for the first half hour would probably use up more capacity than usual.
Most of the overstimulation was caused by being in a busy, noisy environment, working my diaphragm hard to blow a woodwind, tapping my feet to the beat, plus travelling and back. It's always hard to sleep when I've overdone things, but music seems a particularly effective way to trigger the wired-but-tired effect.
Usually I just factor that into my pacing, but this looked like disaster-scale PEM—the sort where the level of lymph gland swelling and sore throat suggested I was in for weeks of feeling terrible. Thankfully it turned out I'd picked up Covid.
This makes sense of the pattern and the experience, but maybe we should be careful about accepting it just because it makes sense. Envisaging PEM in terms of energy might not be helpful; I've started using the word capacity instead, to try and break out of that mindset. (Not very successfully so far, if I'm honest.)
We do feel as if we've run out of something when we trigger PEM, but it may have nothing to do with energy. It could be that it just sets off a signal, in the same way that getting infected with Covid set off a chain of consequences.
Fo what it's worth, the only reliable indicator I've found is an after-the-event one. My overnight resting heart rate goes up noticeably during PEM and illness, and not just for the night when I can't sleep. I don't think it's unusual to see a raised RHR during illness, but it's interesting that it happens with PEM too.
Yes agreed. Not stuck to the concept of PEM and energy or capacity. It does seem like the most often discussed connection but best to keep the mind open.
Slow as a Turtle in. answering.
If getting a red flush would lead to PEM, I would be in deep trouble. It happens to me sevaral times a day, mostly when I use my computer.
I recently measured my oxygen during a flush and it was below 95%, even as low as 92% once.
My brain demanding more blood /oxygen from the rest of my body, by invoking a flush?
Muscle pain even starts during exertion. I had only 1 1/2 minute of aerobic metabolism during my CPET and chronotropic incompetence. The test was stopped by the doc before time was up.
My legs were like rubber bands after the test. I had to lock my knees and hold on to the bike getting off.
That's an immediate reaction building up in the hours afterwards.
Moved post
Does anyone else have PEM-like symptoms from food intolerances? For me, it was hard to tell the difference. Both caused lethargy, brainfog, and maybe pain. I no longer get PEM, but certain foods still cause a similar set of symptoms.
Does anyone else have PEM-like symptoms from food intolerances? For me, it was hard to tell the difference. Both caused lethargy, brainfog, and maybe pain. I no longer get PEM, but certain foods still cause a similar set of symptoms.
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Peter T
Senior Member (Voting Rights)
Before I had eliminated gluten from my diet its effects largely produced the same symptoms as my ME (headache/migraine, brain fog, IBS type symptoms, fatigue, etc), also they kicked in after an almost exact 24 hour delay. So yes they had significant parallels with PEM. Indeed it was only possible to work out what was what once I had stopped work and reduced my activity levels such that individual PEM episodes were clearer and also eliminated gluten from my diet so that any gluten related symptoms triggered by occasional gluten consumption became obvious too.
My food intolerances (caffeine, alcohol, gluten and possibly some aspect of sugar rich foods, such as chocolate, sweets or fizzy drinks) seem to have come on after the onset of my ME, increased in number as my ME deteriorates over the years and overlap in symptoms with my ME and PEM. So in that respect they perhaps could be considered part of the ME rather than a cooccurring condition(s), however my food intolerances also occur independently of my current ME levels, so a gluten reaction is no less when my ME is mild and no more than when it is severe, though I am more likely to break my diet when in PEM and obviously when both a gluten reaction and PEM cooccur their effects are additive.
Gluten intolerance for me has the most noticeable overlap with PEM, but it may be that this relates to consumption patterns as the other food triggers were only ever consumed occasionally whereas gluten was a dietary staple.
(Note - before I had withdrawn gluten from my diet its effects were less clear cut as they were rather an ongoing general, to use a technical term, yuckiness, in practice indistinguishable from my general ongoing ME yuckiness. Also when gluten was part of my daily diet I experienced a ‘cold Turkey’ effect when withdrawing it, severe headaches, nausea, vomiting and IBS type symptoms.)
Kitty
Senior Member (Voting Rights)
Yes, I do.
Even meals that don't contain anything problematic sometimes trigger PEM. Eating can be the proverbial last straw every bit as much as a shower or having to make a phone call, and I'm not severely ill.
I have been thinking about why it's very important that PEM is defined specifically as the usually delayed, and usually lasting more than a day, significant worsening of a person's MECFS that is triggered by exertion.
I think it's vital it doesn't get conflated with all other worsening of symptoms that happens during and immediately after every exertion that can be relatively minor and short lived if we are able to rest enough. I say relatively, because the point is that PEM by definition is being much more ill than our usual.
If we muddle together all symptoms after exertion and call it all PEM, how can we explain to carers, family, and clinicians that something I did today has any relation to how I feel tomorrow?
They see us apparently coping with an outing, and don't see the consequences for us that confine us to bed for the next week. They don't understand the need to stop doing something we're apparently coping well with, or understand the cumulative effect of having a shower on the same day we have a visitor, when we might usually manage one but not both without horrible consequences. They don't understand that someone with very severe ME can be made even worse for weeks or longer by apparently trivial actions that barely register to others as exertion.
When we were new to ME/CFS, it surely helped us when we learned to recognise the triggers that were likely to lead to waking up a day or two later badly crashed. It gives us at least a fighting chance of some level of control. I can't remember whether the term PEM existed when I was diagnosed with ME in 1990, but I soon figured out for myself that if I did a bit more than usual, and pushed through the usual worsening pain, nausea, weakness etc, and kept going with activity for too long, I'd end up having to take sick leave for a week or two.
And how would researchers learn whether there are different things going on with our biochemistry if they don't test before and for some days after an exercise challenge?
I was trying to think of parallels with other conditions, where fluctuations in symptoms are related to identifiable factors.
I remember back to my teens and early adult life having what seemed like random mood swings, with every now and then sinking into a black cloud of weepy depression for a few days. I somehow didn't make the association with my menstrual cycle. Once I found out about premenstrual syndrome, it all suddenly made sense. It wasn't me being pathetic and psychologically inadequate, it was caused by my hormones. Once you know the trigger, it makes management possible.
Similarly with migraines. I have gradually recognised triggers, so have more chance of avoiding them.
I think it's vital it doesn't get conflated with all other worsening of symptoms that happens during and immediately after every exertion that can be relatively minor and short lived if we are able to rest enough. I say relatively, because the point is that PEM by definition is being much more ill than our usual.
If we muddle together all symptoms after exertion and call it all PEM, how can we explain to carers, family, and clinicians that something I did today has any relation to how I feel tomorrow?
They see us apparently coping with an outing, and don't see the consequences for us that confine us to bed for the next week. They don't understand the need to stop doing something we're apparently coping well with, or understand the cumulative effect of having a shower on the same day we have a visitor, when we might usually manage one but not both without horrible consequences. They don't understand that someone with very severe ME can be made even worse for weeks or longer by apparently trivial actions that barely register to others as exertion.
When we were new to ME/CFS, it surely helped us when we learned to recognise the triggers that were likely to lead to waking up a day or two later badly crashed. It gives us at least a fighting chance of some level of control. I can't remember whether the term PEM existed when I was diagnosed with ME in 1990, but I soon figured out for myself that if I did a bit more than usual, and pushed through the usual worsening pain, nausea, weakness etc, and kept going with activity for too long, I'd end up having to take sick leave for a week or two.
And how would researchers learn whether there are different things going on with our biochemistry if they don't test before and for some days after an exercise challenge?
I was trying to think of parallels with other conditions, where fluctuations in symptoms are related to identifiable factors.
I remember back to my teens and early adult life having what seemed like random mood swings, with every now and then sinking into a black cloud of weepy depression for a few days. I somehow didn't make the association with my menstrual cycle. Once I found out about premenstrual syndrome, it all suddenly made sense. It wasn't me being pathetic and psychologically inadequate, it was caused by my hormones. Once you know the trigger, it makes management possible.
Similarly with migraines. I have gradually recognised triggers, so have more chance of avoiding them.
Kitty
Senior Member (Voting Rights)
Yes, absolutely agree.
Jonathan Edwards
Senior Member (Voting Rights)
I think the problem is that you cannot 'define' things that way, @Trish.
You cannot define something as 'usually this'. You can describe it as usually this but not define it as such. When considering one example 'usually this' is no good as a discriminator.
I am sure you are right to emphasise that one of the things that makes PEM a useful concept is its often delayed onset, along with its often (but not always) prolonged course and its different (but hard to describe) character, that is recognisably not just a feeling of having done a lot yesterday.
But in terms of definition I suspect we have to just say that it is a worsening or expanding of symptoms that are not just normal immediate tiredness or delayed muscle soreness following exertion.
If you experience a worsening of orthostatic intolerance with nausea and headache while you are still involved in some exertion does that have to be excluded from the topic of PEM? If you experience these things the next morning for just one day is that to be excluded?
I also think that there is a problem using personal experience to generalise for a group of people with an illness. Each person may have a different pattern of timing and symptoms with the PEM concept still being useful. Syndrome patterns really need to be judged by independent observers (in practice doctors) who have taken histories from many people in thrown words. And even then they get things wrong. Over the years the validity of clinical symptoms and signs has been questioned and quite often found unreliable, as for the so-called 'trigger points' of fibromyalgia.
Peter T
Senior Member (Voting Rights)
Just as ME/CFS, under current definitions is only defined when the impact reaches a specified level of severity even though it is likely that the underlying condition exists in people with milder impairment, I see no problem restricting the use of the term PEM to symptoms reaching an unambiguous level of severity.
Until we have biomarkers for ME/CFS and establish the biological/physiological process under pinning of PEM, for research purposes we should only use the unambiguous manifestations of both with clear presentation.
Perhaps clinically we could use qualified terms such as suspected ME/CFS and potential PEM.
I agree we shouldn't generalise from our own experience. I just gave one particular person's experience as an example.
What I was trying and clearly not succeeding in saying was that PEM is a term created by clinicians listening to patients and discussing with other clinicians, and giving a name to a pattern of worsening way out of proportion to exertion their patients described. That pattern including a delay between the patient doing a bit more activity than usual, and getting much sicker a day or two later, and in many cases that lasted for days or weeks, and the amount of worsening would be way out of proportion to the exertion, which would have not caused any symptoms before the illness.
It is this observed pattern those doctors named PEM. And this pattern that more clinicians writing guidelines and definitions named PEM.
It's been interesting observing people with long covid and their doctors some of whom knew nothing about ME/CFS rediscovering the same phenomenon.
My point is it is this pattern, or phenomenon that is named PEM by clinicians and it's based on observation by many clinicians, and of many patients. It makes no claims about whether it is biologically the same as or different from the everyday more minor worsening with every exertion that pwME experience.
Even Paul Garner, in the days before he adopted loopy ideas, described well his experience of trying to do a bit more in the early days of his long covid, and being confined to bed for days feeling dreadful, if I recall correctly.
@Jonathan Edwards, why shouldn't that phenomenon have a name?
What I was trying and clearly not succeeding in saying was that PEM is a term created by clinicians listening to patients and discussing with other clinicians, and giving a name to a pattern of worsening way out of proportion to exertion their patients described. That pattern including a delay between the patient doing a bit more activity than usual, and getting much sicker a day or two later, and in many cases that lasted for days or weeks, and the amount of worsening would be way out of proportion to the exertion, which would have not caused any symptoms before the illness.
It is this observed pattern those doctors named PEM. And this pattern that more clinicians writing guidelines and definitions named PEM.
It's been interesting observing people with long covid and their doctors some of whom knew nothing about ME/CFS rediscovering the same phenomenon.
My point is it is this pattern, or phenomenon that is named PEM by clinicians and it's based on observation by many clinicians, and of many patients. It makes no claims about whether it is biologically the same as or different from the everyday more minor worsening with every exertion that pwME experience.
Even Paul Garner, in the days before he adopted loopy ideas, described well his experience of trying to do a bit more in the early days of his long covid, and being confined to bed for days feeling dreadful, if I recall correctly.
@Jonathan Edwards, why shouldn't that phenomenon have a name?
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Coming back to this, I find I want to question some assumptions and add some points:
My point, and this is emphatically not based only on my own experience, is that the 'usual' increases in symptoms with any activity for pwME is at a certain level, and the 'unusual' increase in symptoms in PEM is disproportionately much greater, given the small increase in activity.
So of course the type and severity of symptoms when ME/CFS is at its current non PEM level for a pwME is abnormal for a healthy person, and needs to be researched, and the pwME needs to adjust their lifestyle, sometimes drastically, to cope with it.
But the sudden step change from the pwME's current usual symptom severity to a much greater symptom severity and debility is way out of proportion to the slight change in their activity in the preceding days.
That needs to be named, described, investigated and coped with by pwME in a different way to coping with their usual symptoms and capacity.
We need to recogise PEM/crashes as something different from the rest of ME/CFS:
Say someone with ME/CFS does Z amount of exertion one day, and gets their usual symptoms at level Y during and immediately afterwards, and this their usual uncrashed state. If they can do about the same level of activity Z, with the same symptom level Y on subsequent days, then we say they are not crashed, or not in PEM, and their current exertion capacity is greater than or equal to Z.
Say one day they do Z+0.1Z amount of exertion one day, they may experience a proportionate Y+0.1Y level of symptoms that day.
Say they wake up the next morning and for the following several days they suddenly increase to 10Y level of severity with their usual symptoms plus 10y level of new symptoms and have 0 activity capacity to do any of their usual activities. Then they are experiencing PEM.
It's not only about delay, it's about a disproportionate response to a small increase in usual activity.
So no, I don't agree with this:
My point, and this is emphatically not based only on my own experience, is that the 'usual' increases in symptoms with any activity for pwME is at a certain level, and the 'unusual' increase in symptoms in PEM is disproportionately much greater, given the small increase in activity.
So of course the type and severity of symptoms when ME/CFS is at its current non PEM level for a pwME is abnormal for a healthy person, and needs to be researched, and the pwME needs to adjust their lifestyle, sometimes drastically, to cope with it.
But the sudden step change from the pwME's current usual symptom severity to a much greater symptom severity and debility is way out of proportion to the slight change in their activity in the preceding days.
That needs to be named, described, investigated and coped with by pwME in a different way to coping with their usual symptoms and capacity.
We need to recogise PEM/crashes as something different from the rest of ME/CFS:
Say someone with ME/CFS does Z amount of exertion one day, and gets their usual symptoms at level Y during and immediately afterwards, and this their usual uncrashed state. If they can do about the same level of activity Z, with the same symptom level Y on subsequent days, then we say they are not crashed, or not in PEM, and their current exertion capacity is greater than or equal to Z.
Say one day they do Z+0.1Z amount of exertion one day, they may experience a proportionate Y+0.1Y level of symptoms that day.
Say they wake up the next morning and for the following several days they suddenly increase to 10Y level of severity with their usual symptoms plus 10y level of new symptoms and have 0 activity capacity to do any of their usual activities. Then they are experiencing PEM.
It's not only about delay, it's about a disproportionate response to a small increase in usual activity.
We can only go on what recent and current clinicians have gleaned from their patients, and follow their current definitions of PEM. Of course there are variations between patients. If I dare to mention my own case again, my experience of ME/CFS is different from my daughters, just as our experiences of migraines are different from each others. And expanding to all the thousands of others' descriptions I have read here and elsewhere and the consclusions drawn from the many thousands collated into current PEM definitions. They are all about observation and patients experiences, not making any claims to cause or biology.
So no, I don't agree with this:
Utsikt
Senior Member (Voting Rights)
This is my n=1: I’ve had plenty of instant PEM when I was gaslit into exercising 6-24 months post covid. I fully believed that I did not have PEM because it was not delayed. Nobody told me that I didn’t have PEM, they just told me that exercise would make things better.
In retrospect, it’s obvious that I had PEM, because it looked exactly like the often delayed PEM that I now experience when I’m unable to pace properly, 36 months post covid.
I rarely experience an instant onset of PEM. It’s often gradual, often over 1-2 days. Edit: it’s often delayed, but not always.
———
Based on that, I believe that this is as far as we can go regarding PEM:
PEM is:
In retrospect, it’s obvious that I had PEM, because it looked exactly like the often delayed PEM that I now experience when I’m unable to pace properly, 36 months post covid.
I rarely experience an instant onset of PEM. It’s often gradual, often over 1-2 days. Edit: it’s often delayed, but not always.
———
Based on that, I believe that this is as far as we can go regarding PEM:
PEM is:
- A worsening or expanding of symptoms due to exertion
- Not normal tiredness, fatigability, DOMS or deconditioning
- Be delayed by up to multiple days
- Have a gradual or instant onset
- Last for up to days, weeks and months
- Also be triggered by stimuli or sensory overload
- Not be alleviated by rest
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Kitty
Senior Member (Voting Rights)
I can see this point, though I haven't fully got my head around it.
I'd say yes, because PEM as I understand it is delayed. If it's not inevitably delayed I'd need to rethink the whole thing.
What you describe here is orthostatic intolerance. The symptoms happen during the activity and they tend to begin subsiding once you're off your feet. They're not delayed, and I can relieve them quite quickly.
No. That is a delayed response, and for people on the milder end of the spectrum, mild PEM often only lasts one day. The same person can trigger much worse and longer lasting PEM by going further over their threshold.
Where I do begin to get into difficulty is describing how PEM is different from "normal" ME/CFS. Partly because I don't know if it's different for everyone in the same way.
I recognise PEM as a separate phenomenon because it's delayed, it's clearly a reaction to things I've done (which, like an alcohol hangover, wouldn't have happened had I not done them), and it makes me feel acutely ill in the way that non-crash ME/CFS never does. I even look ill—swollen neck glands, hoarse voice, face like a death mask, and my nose runs all the time.