BMJ letter from LongCovid doctors.

[Kitty]

It doesn't mention PEM but this could explain part of the unpredictability of PEM. If you keep to what appears like a safe level of activity, what might be happening is that exercise intolerance develops and the PEM threshold decreases. This exercise intolerance could build up slowly over weeks.

For me at least, my underlying level of energy impairment is probably more important. I don't developed additional exercise intolerance (above and beyond whatever is normal when I start the activity) until the underlying impairment changes.

Typically, I can do low-level activity pretty consistently for several years without getting better or worse at it, and then something shifts and I have to stop. The change is often prompted by getting a virus, after which I don't return to the level of function I had previously. It can last anything from six months to eight years, after which I improve again slowly.

 

[Barry]

It doesn't mention PEM but this could explain part of the unpredictability of PEM. If you keep to what appears like a safe level of activity, what might be happening is that exercise intolerance develops and the PEM threshold decreases. This exercise intolerance could build up slowly over days or weeks. I think something like this would explain a lot, since I tend to have periods of weeks to a month or two were I'm apparently capable of doing more and they often end with bad PEM episode.

I've mentioned this once or twice here in S4ME before. My wife typically paces very well, and in doing so avoids PEM to a significant degree. Still gets payback but not too bad. When her pacing is less successful then she gets PEM with a vengeance.

But lack of significant PEM does not necessarily mean a person is not prone to it. It may just mean they are successfully avoiding it.

 

[Mij]

But lack of significant PEM does not necessarily mean a person is not prone to it. It may just mean they are successfully avoiding it.

We all have different 'energy envelopes'.

I believe that my very first PEM experience was from climbing my stairmaster for 25 minutes in 1993 on a day I was feeling 'ok'. I didn't have any other symptoms except severe fatigue/weakness in my calves for 6 months. It was when my health improved and I started running again that the PEM intensified- the point of no return.

So the more we overdo, the worse PEM will intensify over time.

 

[Kitty]

So the more we overdo, the worse PEM will intensify over time.

It was when my health improved and I started running again that the PEM intensified- the point of no return.

So the more we overdo, the worse PEM will intensify over time.

This makes me wonder why some can recover from accumulated PEM – eventually – whilst others seem to reach that point of no return and never recover their previous function. We so much need to unpick the mechanisms underlying this.

 

[Mij]

This makes me wonder why some can recover from accumulated PEM – eventually – whilst others seem to reach that point of no return and never recover their previous function. We so much need to unpick the mechanisms underlying this.

But do we really know if they've actually recovered from accumulated PEM? I felt as though I recovered from PEM after a few days, but we don't really know for sure because it can take years to recognize the 'damage'? It can present itself in different ways. For example, my cognitive issues only started after experiencing PEM many times. I never had those issue before, I was shape as a knife.

 

[Kitty]

But do we really know if they've actually recovered from accumulated PEM? I felt as though I recovered from PEM after a few days, but we don't really know for sure because it can take years to recognize the 'damage'?

With regard to anyone else, I don't know. I suspect there are many different patterns.

I've got a nearly 45-year history of ME of my own to look back on, though, and I do appear to recover – eventually. My overall level of function is far better now than in the early years, or at many different points during relapses. (I fell ill at the beginning of 1976 but wasn't diagnosed until 1999, so I did drive myself into relapse a few times by not knowing what was wrong or understanding that I needed to pace).

It can take a looong time to recover previous function, though, so I've tried to pace assiduously since my diagnosis. Because I swim it can sound as if I do an awful lot, but it's not really the case. I use a powered wheelie, so I'm doing none of the outdoor walking that most mild/moderate ME folk do. Swimming is much easier to measure and keep under review than walking, as you know exactly what distance you've covered, how often, and how quickly. It's also easy to stop completely if you feel that your function is going downhill a bit, which isn't an option with walking if you happen to need groceries or whatever!

 

[Snow Leopard]

So true of my wife also, in conjunction with missing seeing the places you can only get to by walking there.

Or riding a mountain bike.

 

[Barry]

“Pushing through” is not part of GET. It is about establishing a regular baseline and then gradually increasing without incurring severe PEM and thus going back to square one.

This is self contradictory. For many pwME "gradually increasing" will invariably be reaching a point where they are pushing through. I suspect the means by which some people manage GET "without incurring severe PEM", is simply by dropping out of the treatment or clinical trial. And then they conveniently drop off the radar of people like SW.

 

[James Morris-Lent]

This is self contradictory. For many pwME "gradually increasing" will invariably be reaching a point where they are pushing through. I suspect the means by which some people manage GET "without incurring severe PEM", is simply by dropping out of the treatment or clinical trial. And then they conveniently drop off the radar of people like SW.

Right. It seems to me that his definition of 'Real GET' here is 'reconditioning without getting PEM' or something like. This makes the definition of the method and goal functionally the same - so by definition 'Real GET' works 100% and failure must be caused by 'Wrong GET' either due to practitioner or patient fault.

How does anybody (re)condition without 'pushing' as we would reasonably interpret the word?

 

[Philipp]

It is incredibly telling that he:

a) Seems to think anybody knows their daily PEM threshold on any given day (as if that wouldn't fluctuate wildly enough to leave people guessing every day)
b) Seems to think gradual increases are beneficial or even possible (as if it was known to be inherently beneficial to do more stuff)
c) Seems to think anything below 'severe PEM' is acceptable (as if anybody knew how that works out for people long-term)

This seems a bit like telling someone who is obese due to medical reasons to go be less fat. Sure, the goal seems to be like a good idea intuitively and conceptually but what I'd really wanna know is how to actually go about it. If we worked out a reliable and practical solution (e.g. if we got down how to pace properly via pulse measurements or whatever) I'd actually be completely on board with the concepts - possibly not with how they are peddled by people who apply those things in real-life settings but I am totally down to do as much stuff as I can even if it has a null impact on my long-term health to simply escape the violent oppressive boredom that comes with this illness. Hell, if I knew that suffering through mild and measured PEM after overdoing it a bit on a good day would be beneficial for me in the long run I'd probably do it but the thing is that we neither know how to dance on that particular knife-edge without fumbling nor do we have any good reason to presume that this won't hurt us over the years.