If you go to this page:
http://eowynridesagain.wordpress.com/game-basics/ and scroll down to the "Power-ups" section, you will see the list of activities I developed that I could do without hurting myself.
One of the ones I ended up spending the most time doing was coloring. Buy yourself a box of crayons, Google "coloring pages for adults" and go to town! I also spent a lot of time walking outdoors when the weather was good.