I went to a spin class last night for the first time. Pretty cool. If you are ever wondering what a normal bike workout is like, it's just like a spin class. Maybe not quite as hard and you don't have to dig quite as deep in a spin class but it's similar.
On the plus side, even though I haven't ridden a whole heck a of lot (or at all) I feel pretty bike confident right now. I've done enough long rides that rocky point and alcatraz shouldn't present much of a problem. Need to run. My swimming is coming along nicely.