I've had FMS for over 10 years and find mild exercise helps. As does treating my low thyroid.
I've had it since the teenage years, Gail. I also have been diagnosed with hypo-thyroidism, Meinere's Disease, Epilepsy (life long), the jaw thingy (I never can remember that one), Spondylitis of both the Cerival and Lumbar regions on the spine among other things.
It's not any fun and light excercise is good, but since I like to walk I sometimes over do it. (But then who doesn't especially when it comes to shopping.)