seriously that is a problem, and it sucks that you have to endure for most of the run. i bet it hampers your performance! :-\I usually run in the morning, at 10-11am. Just eat a bit to get the metabolism going. But I shit from the previous day and I usually have to shit everyday, so I'm not constipated. I probably always have some shit in me from eating, running lubricates it all and gets it going making me shit earlier.
can't you take something to prevent this from happening? ??? a med or a special diet that makes you constipate :P (or how about don't eat a lot that day?)
either that or you can always just... u know... "let go" :angelspoiler (click to show/hide)(http://i36.tinypic.com/s1kuip.jpg)[close]