My question really is about the semantics of 'crash' and 'PEM'. I guess I used to use both these words somewhat interchangeably and wanted to ask PRers what they think.
In my experience with ME, PEM, or a worsening of symptoms, happens after mental or physical overexertion and only when I have too many periods overexertion over a short enough time without sufficient rest (or a continually long overexertion) then the PEM continues to build until I have a crash. Rarely too I've had crashes that seem to have come out of nowhere and didn't appear to be preceded by PEM.
So these words are distinct but related phenomena to me. What do you think?
I’ll be honest I use both in ways in my head that apply to very distinct things. A crash can be caused by a virus, after I got first vaccine, as well as PEM type stuff. Though I guess those are exertions. Something eg building noise can cause PEM but the amount, frequency vs breaks can either ‘reduce my envelope’ or put me in a crash and then do exertion on top of that if still going.
PEM doesn’t have to be an ‘all out crash’ but is ‘post exertion’ and if a defined cause you feel (and can predict) when it ‘hits’. You can have rolling PEM where you layer overexertion onto effects of prior overexertion. Once it’s a crash and eg you’ve got noise from building works/are talked at with questions or are stranded somewhere uncomfortable etc that’s in need of a term in itself.
PEM being the ‘hit’ 36hrs (sometimes 12hrs) later that can wake me up in pain in the middle of a deep sleep as my body suddenly feels like bone-deep aching EVERYWHERE. Easy and straightforward this example where you know you’ve got a ‘trip out’ and you know it’s so much over ‘you’ll deffo pay for it’ even if rest around it to limit that. Here is where a crash = PEM. And the crash to me starts when symptoms hit and if I’m not in bed I need to get there.
of course to a layperson I’d call that a ‘crash’ because they get it as ‘out of action’. from a ‘what is it’ to someone understanding cause and effect I might say PEM.
But a crash also used to be when less severe and trying to work ‘a timed crash’ by taking a week off every six weeks just to be stuck in bed - if I left it too long between it would hit anyway or I’d be doing the reverse ‘ascent of man’ (walking more slouched each day).
I could have PEM where I’m not crashed out for days but ‘carrying it’ and have the symptoms but at a lower level from a few days prior. I’ll tell laypersons‘I’m in PEM so keep it brief and quiet’ if something urgent crops up.
What I don’t know to do with is the ‘system specific’ exertion induced debilitation and symptoms eg cognitive neuro or arms more immediate impact re PEM eg I immediately can’t support my own arms for hours if I use them too much
and the fact that ‘robbing Peter to pay Paul’ where I’m overdoing it constantly (either not quite enough with just enough breaks to still push on rather than being ‘out’ with PEM or not giving FULL recovery time from PEM just enough I can function to the next urgent thing in diary) but know just enough.
These eventually lead to crashes and relapses but as it’s more cumulative it’s not as distinctive as PEM and which of these it is based on what I’ve been doing (and payback ‘I’ve got coming to me) + how long it will last and how confident I am I’ve not done permanent significant deterioration that just needs ‘resting off’ like flu bout or glandular fever episode
