I'm a participant in the local search and rescue unit, and one of the
things that is highly advised for all of us, esp. those on the dog team,
is to keep a log book of training. Each time we practice w/ the dogs,
and each time they actually go on a search, as much as possible is recorded
about the event. (Did the dog have enthusiasm? did it chase squirrels and
birds? how far away was the alert? how was its refind? etc.)
For my horse i (try to) keep a log book of our training as well, whether
for trail or not: did he spook more or less on this day? how far did we go?
how long did we ride? how was he when we were done? was he interested or
bored? how did i feel afterwards? how's his back? etc.
Most of the time "his" lack of performance is because of something i've
done wrong. While i haven't done a lot of endurance training (yet), this
personal training log is something that i will keep.
There's a catalog out of Great Falls, MT, that sells different sizes of
waterproof paper notebooks. That's what i use for my various logbooking.
I'd think that if you have the luxury of a crew you could keep your
personal log book w/ your crew, and record your own info.