Just came across this; not sure how authoritative it is but it gives a simple explanation linking pseudo flare-ups to increases in body core temperature.
A useful article, thanks. A good reminder that relapses are not always what they appear and to make sure and look for non-MS causes.
I do disagree a bit with the exercise thing - pushing yourself to the point of a pseudo-relapse is never going to be nice, but it won’t actually do any permanent damage and not pushing the boundaries may result in a downward spiral of activity.
If I’d avoided pseudo-relapses when I was still training loads, I would never have achieved all I did in that sport. And it definitely didn’t do me any harm; in fact, I’ve even told by that it’s helped me to stay as well as I am.
Karen x
Hi Karen,
what sport do you do?
Catherine
I used to do ballet and then, with a couple of years overlap, moved into taekwondo, pretty seriously. I had to give it up in 2010 when my MS decided to up its game 
Kx
Thanks Karen. Do people tend to recover as dramatically as it came on with a pseudo relapse once the temperature falls back?