I have never ever been a big water drinker. I seem to be able to get by with very little water - I have run for up to 2 hours and still not really wanted water at the end of it. But yesterday, I was trying to do some running at a certain heart rate - and had great trouble trying to keep my HR from rising during the run. Did a bit of Internet research - and decided this morning that I would force a fair amount of water into myself as soon as I woke - and went for an hour run an hour later.
THIS time , my HR seemed to me to be much more "controllable". I was able to run "easy" for as long as I wanted without having to stop to walk because of a rising HR. It might be coincidence - or the fact that this was my second run after a layoff caused by a head cold - but I am going to continue to force myself to take water even when I don't really need/want to and see how it goes. I have been meaning to buy a water belt for running longer distances , but in this current heat , it may also be useful for shorter quicker runs.