Do those help with keeping exacerbation of CFS symptoms as part of PEM at bay too, or did it only help with muscle issues, etc? If it helps with preventing PEM in general I would be very interested in trying it. I do have OI too.This was corrected for me after I started midodrine and florinef (OI treatment). I think my PEM varies too and it used to be as fast as yours. In my opinion I think PEM is after ANY activity, exercise included.