I usually have some water before a 5k on treadmill but not during, as I can't!
10K race, I usually have a few sips of water at the station.
& long runs I always have water with me!
So maybe it's not how often I drink but How Much! I always try to drink 2 litres a day( I think that's the daily average?)
I just thought, people hand in Jelly Babies during races, that could be why?