i only use my north face bladder-backpack when i go on crosscountry runs. that's when i just head out into the woods or maybe take a train or bus out to somewhere in the midlle of nowhere and just see how i get back home. so i have no idea about the terrain and there will usually be the odd hill or so en route.

even when i do my "regular" long runs (i.e. 30+k at an aerobic pace, occasionally picking up the pace in the end for the last 5k or so) i won't take anything to drink along. the only time i actually regularly drink while training is when i do (high intensity)speed work. but that usually takes place at the track so it's no problem just leaving a sportspottle behind somewhere.

what i do before my long runs is just drink a glass or two of water and i'm good to go. i actually read in some running magazines that it's actually beneficial not to drink during training, so that your metabolism gets used to running low on fuel. of course this only works for aerobic runs. but that's (usually) what "long runs" are. this way you condition your body to run as efficiently as possible, which will aid you when it counts: during a race! and if you make sure you fuel up regularly during that race you will be able to sustain your race-pace...

but of course you guys all know how it is: for almost every theory A there is another theory B that states the exact opposite of A. and of course people are different. a friend of mine with whom i go mountainbiking every now and then always said i'm like a human camel!