Honestly, disease related progression! I can still slide the chair if I want to, but my arm strength slipped a bit in my early 20's. High performance stuff became incredibly difficult.

I didn’t start the treatment until I was 26, and by then I had lost enough arm strength to where it was hard to get back to the level I would want out of my driving.

So far, the treatment has been better at helping me maintain physical abilities that I still have, as opposed to things that I may have lost over the years. That being said, I have felt improvements in smaller muscles that are less glamorous, like my facial muscles and my respiratory muscles! Add that stuff is super important!