that usually the case. if you have the patience to plow through
the link, there's quite a bit of info on the subject
http://www.arthurdevany.com/members/?cat=5
The part about the Top Ten Reasons Not To Run a Marathon.....
the first eight were well backed-up, but the last two were
anecdotal and may not really mean anything.
That said, it's true that marathons can be hazardous for those
who are not well-prepared for it.
I lost a LOT of water through sweat..... I must have chugged
down at least two liters of 100 PLUS throughout the run, and my
weight still dropped by two kilos.
And my digestive system got messed up.... those two liters of
100 PLUS just kept sloshing around my stomach throughout the run
and refused to be absorbed. It was only after the run that the
water started getting absorbed.
I could only start peeing about four hours after the run, and
phew..... let's not get started about the stench..... 
