Get help from others but remember all the pieces are different and may take time to fit. Heat, Cold, Electric stimulation, Water therapy. Morning, Noon, Night. If you are unconditioned make sure you understand realistic goals. Some individuals can't walk because their back, hips, or legs hurt too much.
Water can stretch, strengthen and condition the body without risk of injury and pain.
You will not hurt yourself if you follow a well developed progressive program. Rather, the flare ups are due to some other cause. However, you may need to modify your exercise program during the flare up. It is important that you continue your exercise program in spite of the flare up. Once you're deconditioned, it becomes even harder to reactivate the muscles.