He just felt like running

Clock a zulu warrior. It's still inexplicable that hasn't been done besides the fact they won't let you.

Jeez I can barely run down the block let alone run an entire half a day

So on average you expend 100 calories per mile you travel. This is the roughly the same whether you run or walk. That makes this 10000 calories burned in 11hr:20min. That's insane. He'd had to have been eating and drinking while running at that speed.

But why?