I am able-bodied. In 1988 I bought a handcycle from a disabled friend. I didn't keep it very long. Back then they were slower than ever, due to improper gearing and the crankarms not being in parallel like they are on modern handcycles. Having the crankarms in parallel is much more efficient.

I was asked to test ride a modern handcycle by the LBS I bought my Worksman Port-O-Trike from (they know I work on my own bikes so they trust me ). They had adjusted the gears and wanted to make sure it shifted ok. This wasn't even a high-performance model and it was much faster than that old prototype I used to have.