There's a linked video on metafilter of a persistence hunt -
http://www.youtube.com/watch?v=fUpo_mA5RP8 (dunno if it's in the US) Its worth watching to see how they track the antelope and get into another level of consciousness.
It's made me want to get into more endurance running..it seems pretty compelling to me that this is a way hominids and early humans would have hunted.
The vid says that the runner chases the antelope for 8 hours. Some of this would be walking, stopping and thinking but still a feat of endurance.
I was wondering if you had any thoughts on which types of run would simulate this. I was considering going for a half marathon. Maybe a more accurate way would be some event with walked sections and thinking that takes longer...orienteering?