I can't exercise because I am barely able to even move around the house. There were periods / fluctuations where I was able to exercise and try to keep healthy. At the current time, its a complete no-go for me, and i refuse to push it.
My personal opinion, is to do a few tests on yourself. Like force a session of exercise and monitor yourself. Because everybody's degree of impact of this illness is different and widely varies, you may find that you CAN do a certain exercise for a certain period of time, etc.
That way at least you know and will be able to stop wondering about
Of course, there will be many who are strictly against pushing or trying. But we all have different tolerances and pain levels and symptoms and causes etc. You never know until you try. Keep a diary of it.
At least its better than doing nothing, wasting time wondering, and letting life slip away. Myself, I will take my own advice when i am a little better. For now I have a major flare of symptoms and am incapacitated. Perhaps in a few weeks I will have a good few days and can try and see what I can do.
Some people find walking in the swimming pool is gentle and good. I have done that a few times.
There are the fit normal people doing exhausting laps around me in the other lanes, and there I was just walking up and down the lane.
It was good.