I am glad you thinking of doing something active, you can trust me on this, you will be really happy and your body will be happy as well.
I have not only JRA, I have Lupus and MS, and also damaged spine due to failed spinal fusions and as a result Arachnoidities. I tell you this only for you know that I know what pain and luck or energy is. In my worst times, I still wake up and do stretches, walk around the house 10 min here, 20 min there and than I am back to bed. On better days, I go to do yoga, I try to walk around the house as slowly as can be (I also have dropped foot due complications). My RA Dr insists on moving, she said gaining weight and luck of activity, this what kills people with health issues, not the disease itself.
When I was healthy I did very advanced yoga; after I got ill, I told my teacher about all my problems and restrictions. Good and knowledgeable yoga teacher knows all about spinal damages and other restrictions and suggests herself what you can do.
During class, she tells everyone what poses we shell do and if this is not for me, she always say: Moldova, not you. There are plenty of healthy and reasonable poses, stretches we all can do. Just look for someone with good experience.
All my life i was wondering how my poor mom moves at all, how she gets up every single morning (now she is 75) and cooks, goes to work, does heavy dirty house work, takes care of dad and 3 kids. She has the worst case of OA, it started for he at age16, by 30 her spine was completely affected by OA, she never can bend, all spinal nerves compressed; scans show "bone on bone" on every joint of her body. Moving was bringing her a great deal of pain, but boy did she move!
I asked her once how can she do what she does with no time in bed during the day? She said if she wouldn't push herself every day to do what she does, she would be long time ago bed ridden. All her doctors was wondering knowing how bad she is, they didn't believe that she is capable of doing all this every day work. I took it from her, I know how good this for everyone and don't look for excuses for myself, just push and go...
My PM told me once that this is a miracle I am don't need anti depressants. Many of his patients who have lesser health issues than I do, they all on anti-depressants. What is my secret?
I told him first of all, my family and friends; their support is priceless. Than, I don't have time to get depressed, I do what I can and get on that couch only when my pain over 7. And even if I am in bed, I read. So as you see sweet heart, you still can do a lot to make your life quality better.
I am on Orencia shots every week. I had many different infusions with biologics, shots, pills, steroids, but unfortunately no remission for me. Only once I was lucky for a very short time; right now I was told by my DR nothing can be done for me RA wise. I asked if I can try Orencia shots (they didn't have them when I had Orencia fusion) - what if? No miracle for me so far, but maybe one day they will find the way to help those with advanced cases of RA.
Best luck to you, take good care