ride the bike. I also had the chance to do alot of uphill hiking and then ride the bike down. hiking downhill is not recommended. I take it you don't have too many mountains to hike in FL. Anything to work the quads!!!! it took me awhile to get it back to the same size as my 'good' one. I am 11 months out now and am sooo ready for my first ride since last may! also the balance board helps alot.
best thing to do is find a physical therapist that is familiar with wakeboarding. They already know where you were, and what you want to get back to, and are more liable to have your best interest in mind.