I find something different: yesterday I did a long run (19 or 20 miles) in quite warm weather, drank plenty of water (about 5 pints?), but didn't pee (or feel any need to) for hours afterwards. Then I had to get up twice during the night, as it all caught up with me.
I tend to think that intense exercise causes the body to secrete some hormone that temporarily reduces kidney activity in order to conserve water?
PH ought to know!