Yes..I came down with CFS in my late twenties ( now 68). Never bedridden until in my 60's for a few weeks, but now doing better..But during a remission when I was 47' I started exercising slowly at a gym with a trainer. The first two weeks, I got mild symptoms but was able to slowly push past that to going regularly to the gym three days a week for THREE YEARS and I felt FABULOUS like 16 years old again and NO symptoms. THEN I felt so well I started working too much and missing days at the gym. As my body got weaker and the stress and work increased I CRASHED HARD! Became VERY SICK, the worst I had ever been. Took me four years to recover, but I did! However, I never returned to the gym and have endured symptoms on and off ever since. So the answer? Maybe I could have kept the exercise up if I hadn't over worked, over stressed myself, but I didn't know it could come back and I'm A type personality and when feeling good, hard to slow down. So many things I like and want to do.
So now I can't again,.....going on four years this fall. My sofa is my best friend now. I may get better again, I don't know as now my age is against me, But trying to learn to accept what I can do, and pace. D-Ribose has helped but not a cure.
Good luck to all. Know that no matter how good you may feel and get, it can ALWAYS return if not careful. But many can recover and I DID.. But In my case, I blew it.
Yvonne