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Is there any evidence that deconditioning alone causes pain and fatigue?


Senior Member
As of 2003, Simon Wessely was still advancing the theory that PEM "may be caused by eccentric muscle contractions leading to local microtrauma in muscles subjected to excess work (as occurs in anyone undertaking exertion after a period of inactivity)." Wessely S, Chronic fatigue syndrome. Psychiatry 2003: 2; 20-23

This is somewhat absurd, since the delayed onset muscle soreness that results from eccentric contractions will cause pain only when the affected muscle is being used, not when it is at rest. His theory also does not account for non-musclular PEM symptoms.

I think there's a really good reason that orthopedic specialists and even physiotherapists are never included in the papers where those sorts of assumptions about PEM are made - it's just so blatantly wrong at such a basic level as to be completely ridiculous.


Senior Moment
Sussex, UK
I missed this thread completely, @oceanblue . That is a brilliant piece of writing. Deeply impressed!

I find it very frustrating that the PACE team have never even tried to test their two primary hypotheses, fear and deconditioning. It reminds me of a lecture way back in Physics, where the lecturer scraped a piece of chalk across the board producing that ear piercing screetching noise. His hypothesis was that the surface of the blackboard was covered in gremlins, and when the chalk ran over their heads, it tickled them, and they squealed. PACE would simply have accepted that as an obvious explanation, covered the board in oil, and concluded that the lack of noise proved that they had been right all along. Of course, the board would then have been unusable, but that's science PACE-style.
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