9 Exercises for Rheumatoid Arthritis of the Hands, by Dr. Andrea Furlan

Many people with rheumatoid arthritis tend to avoid exercise because they’re afraid that the activity might worsen their joint pain. But exercise is one of the key treatments to help reduce the disability often associated with rheumatoid arthritis.
Regular exercise can boost strength and flexibility in people who have rheumatoid arthritis. Stronger muscles can better support your joints, while improved flexibility can aid joint function.

Exercise can reduce fatigue and ease depression. And better overall fitness helps prevent heart disease and diabetes, two life-shortening ailments that often accompany rheumatoid arthritis.
Rheumatoid arthritis also accelerates the loss of muscle mass that typically occurs as people get older. That’s why it’s important to do exercises that will build muscle, in addition to aerobic exercises, which strengthen your heart and lungs.
https://www.mayoclinic.org/diseases-conditions/rheumatoid-arthritis/in-depth/rheumatoid-arthritis-exercise/art-20096222