When I was a teenager (again still in the desert), I did a lot of work outside. It was common to consume well over a gallon of water during a work day and STILL be dehydrated. There was a saying that was often repeated when working outside:
If you aren’t peeing; you’re dying!
When I started riding motorcycles at the track I was amazed how few people understood hydration. During the summer months a large number of crashes are directly attributed to lack of water. I would see riders in my pit and recognize the signs of dehydration. Suggest to them that they drink more water they would shake their heads and tell me that they had a glass this morning and they were fine.
When I race in cool temps (below 100F) I pack 8 liters (2 gallons) of water per day. Normally I consume all of it.
When I race on hot days (well over 100F) I pack 12 liters of water per day and usually drink even more that what I brought.
You go through a massive amount of water and still only urinate a couple of times per day. My goal is to out on track with the urge to pee. When I come back from the track, I no longer need to pee and am again thirsty.
Where does the water go? That is the subject of the rest of this article.