When you have rheumatoid arthritis (RA), it is important to do what you can to maintain or, even better, improve your fitness level. Regular exercise can help you preserve your mobility, sustain your health, increase resilience, improve your sleep, and help ward off feelings of hopelessness and depression. You can do a lot from home. Before embarking on any form of exercise, be sure to check with your doctor. You may also get some exercise ideas from your physical therapist.