Adding to your conversation with twitchy. All weakness is some sense perceived until confirmed by the neurologist. I knew my ankle was weak before it was confirmed as clinical weakness but if I had a neurologist by my side when it started it would have been confirmed. If a neuro examines you and finds no weakness then it really is perceived weakness. And the thing with ALS is the weakness occurs because a Signal does not get through. I saw a great analogy. It is like the muscle receives a telephone call to work. One day the call can't get through and bingo it does not work any more. Sometimes surrounding muscles can take over for a while. Sometimes they can't