Good topic!
I too loved to swim - just being in the water, weightless, did wonders since my knees were giving me fits. But, like you say, I guess the reaching motions are not good, so I did the best I could with the little I had to work with, which is treading water. It's a great way to gently use every muscle and improve circulation - especially in the legs.

I'm ever grateful that we have access to a pretty nice therapy pool. I enjoy the warm temperature - very soothing on the muscles and I use the little aquatic 'toys', especially those little floating doo-dads that look like little dumbells, barbells