Physical therapists may be the experts, but too many of them work by the "no pain, no gain" formula, where more pain now equals less pain tomorrow. Unfortunately, as we all know, fibro often sends that formula down the tubes.

Only you know what your threshold is, and you need a way to make that clear to the therapist, so that when he/she insists you do one more minute of exercise, and you say you can't, then they understand that you're not just being wimpy. You know what those last few sit-ups will mean for you tomorrow, and that it won't make anything "better".