I just thought I'd add this: until quite recently I thought that due to a pretty severe heart condition that I was in bad physical condition. I picked up a book to read on a long car trip that changed my perspective somewhat:
http://www.amazon.com/No-Excuses-Congenital-Champion-Wrestling/dp/0895260115
here's a little more that I wrote about it:
http://www.fundamentalsoffreedom.com/fswforum/index.php?topic=6625.0
Since finishing that book I have decided to train for and run a 5km (about 3.1 mile) race within the year. Previously I had never run farther than 1.5 miles.
Like the title of the book says: "No Excuses"! Not for me anymore. Henceforth, I'm only as disabled as I decide to be.
-Herk