Hello Everyone,I found a thread on this site discussing the difference between "perceived" weakness and "clinical" weakness, but I'd like some of the old-timers and newbies (like me) to comment on this distinction. From what I have read, "clinical weakness" is simply weakness that shows up on a clinical exam, like you can't squat down or you can't walk on your toes. It is real weakness that has been caused by damage to the muscles, peripheral nerves, or central nervous system. It is real because of the damage that has been caused and it is obvious to a neurologist.While BFS does not cause clinical weakness in the sense that you may fail a neuro's strength test or have damage to your nerves, it does cause "perceived" weakness which is often called "exercise intolerance." My question is, "How is exercise intolerance different from weakness?" For example, my BFS causes my forearms to become easily fatigued, which I describe to others as being "weak." They are a little stronger now, but six months after the onset of my symptoms, my forearms felt exhausted simply from typing a sentence. Also, my legs felt weak and it seemed like a burden just to climb the stairs. It felt like I had always just finished 100 reps of wrist curls and 100 squats. The weakness may not have been clinical, but it was (and is) very real.I just want to clarify that "perceived" weakness does not mean "not real." It is real, but it is not clinical, it is not permanent, and it is not caused by damaged tissue. Knowing that I felt weak, I was not encouraged by comments on the site like, "Don't worry about it if you have no weakness" or "neurologists don't care unless they see weakness." I believe a lot of us on this site who have been diagnosed with BFS do have real weakness. Maybe we should just use the phrase "clinical weakness" when referring to the kind of weakness that indicates motor-neuron disease. Using the word "perceived" with BFS weakness seems to me a little misleading. Is it wrong to say that weakness (not clinical) is one possible symptom of BFS?-Joe