The reward of an ultramarathon is doing something you (and many other people) don't think you can do.
It's "fun".
It's "fun".
Type 2 fun is my favorite way of describing it. Usually starts with good intentions, it’s miserable while it’s happening, but afterwards the mind convinces itself that the experience was enjoyable.
I started our ultra running because I wanted the achievements. That would never have sustained me doing it over the long term though. Eventually I learned to slow down a bit during the races so that it was less of a sufferfest and I could enjoy them more in the moment. Now just being "out there" is the reward.