Yes, thank you, your definition helps. I definitely have what you describe, though it depends on how much I do and what I do, but the doctor who did the Neuropsych evaluation for my brain damage testing way back in 1995 said my shortened physical endurance is because I have severe damage to the part of my brain that handles fine motor skills endurance.
Was it the car accident head injury that caused this like he says, or could CFS have caused this damage? I asked him, and he told me emphatically that I did not have CFS and that my brain damage patterns were totally consistent with the type of head injury I had sustained. In fact, he feels everything that is wrong with me is due to that accident, since I should have died from the head injury. He isn't buying FMS, CFS or Lyme!
His adamant opinion helped me with disability, since he told them I was permanently and seriously injured, that he could not believe I was able to get out of bed, let alone walk, and they had better not be reviewing me and wasting the taxpayers money. That got me ten year disability review, which was a huge relief, as those of you who go through reviews every 3 years no doubt know.
He told me that CFS presents with a distinct pattern of brain damage unique to it and only to it, that he would feel confident diagnosing CFS based just on seeing a person's neuropsych evaluation! I have learned the hard way never to trust just one medical opinion on anything and that "opinion" is the key word there. I may never know the answer to this.
FWIW: Just to throw in another monkey wrench, a nationally known psychic gave me a reading for my birthday in 1998 (it was a present from my spouse), He had no info on me except my name and credit card number and I made sure beforehand that I had never charged any health related items or other revealing things on the card I used.
He asked me what I wanted to know about and I said my heatlh. He immediately asked me if I had heard of Chronic Fatigue Syndrome or Fibromyalgia. Not wanting to help him at all, I just said that I had heard of them. He said: Well you have both of them". I aksed him if they were not the same and he said no, but many people have both. I asked him if he knew the causes, and he said they ae both caused by viruses and that many new viruses we have no resistance to are being let out into the air as the rainforests are burned. That was a new one I had not heard before.
You may think, so what, that was just a good guess as to what was wrong with you. I thought it was pretty specific. But, he said several other amazing things and he predicted something that I felt was so impossible that I laughed at him. A year later, it came true, just as he said. A few other smaller things have come true also. In a half hour phone reading, he got only one thing wrong and it was something he could easily have gotten right if he had made any advance attempt to find out about me. Knowing where my area code was located would have prevented the one mistake he made. Note that he did not mention Lyme....hmmm.
Make of it what you will. I still don't know if I have CFS (I empathize, Kolowesi). Maybe labels don't matter, just symptoms. Of course, if XMRV pans out as THE cause and they develop a reliable test, then we can know for sure.
When I was studying Naturopathy, all of the people in that field I encountered believed that CFS and FMS are the end result of systemic breakdowns of the body's systems that can be caused by many, many different things.