Wheelchair Dancer has written some great stuff about what fitness means for the disabled body. Too bad (okay, not really) I already turned in my 'alternative PE' writeup!

It seems [my trainer has] been getting questions about his work with me. What are his goals? How is he measuring progress? Why haven't I made progress? What are the deliverables? What is he doing, in what order, and why? Where is his plan? ARG, who has disability experience, knew exactly what to say. Disability is different. You don't train a disabled person like me with standard fitness goals. I am making progress. His goals were never to have me up and running marathons. Nor was he attempting to have me lose 10 lbs or so. You can't measure stability and injury prevention in the same way as you can raw strength. They can't assess my progress without asking me, because I know best how my body has changed and I alone have to live in it. He essentially shrugged their concerns off.

...

None of this is visible to the outside world, because to them, I have been doing the same exercises for the past 6-7 months with no discernible sign of improvement.

I could quote the whole thing, but ... nah. Go read it.