The dude is a freakin' machine. There's a short film (13 mins) called 'Kilian' at https://www.youtube.com/watch?v=7eVBrMcflDE which made it into the Banff Film Festival last year. Worth a watch if you want get a better feel for how he travels and his thought process. Food for twenty hours in the mountains? Oh, I'll probably take 4 Snickers or something...