I get tendon pain in my wrists from paddling too. I keep it under control with a weight resistance exercise.
Once/twice a day, I hold a 15 lb dumb-bell in my hand with the palm up. I lay my forearm along my thigh while seated in a chair. My wrist is just off my knee. I lower and raise the dumb-bell to the max in either direction 30-40 times (till you can't do no mo). If it hurts, I stop, but usually it makes it feel better instead of worse. Of course, I switch hands and do both wrists.
BTW, this is a standard weight lifting exercise for strengthening forearms and wrists. You will find it in most any comprehensive weight lifting book. I do NOT like doing this exercise with both hands on a single bar bell together because it misaligns the wrists and leads to wrist pain instead of helping.
This has really worked for me. I think it works because it strengthens the muscles around the wrist so they do a better job of taking the load, keeping the wrist properly aligned.
Try it, the worst that will happen is beefy wrists 
Craig
