I know this might sound cheesy, but it might work...?*** Have you ever gotten one of those mail order catalogs in the mail, like Harriet Carter, etc.* They often times have lots of little gadgets and products that are marketed to older people, or ones that you think"why would I ever use that"?!** Well, in just about all of them, I have seen this little device that is link 2 bicycle pedals mounted on a kind of block.* To use it, you sit in a chair and pedal.* Maybe something like that would work for you.** Oh, and you might want to reconsider the exercise ball....they are REALLY big, and the dog probably wouldn't look at it as a toy, so you might be o.k.** Just want you to recognize if that is a realistic option for you after all, because I know that I myself will often think and idea won't work if I am in a "self-sabatoging" mind set.* Good luck with a solution!
-Sunny