The most perplexing: How is it possible to come to believe water is bad for athletic performance, especially long distance running? Not only water, but seemingly distrusting any tangible amount of any liquid?
Exercise-associated hyponatremia is an issue for endurance athletes. If you drink too much water it can throw your electrolyte balance off which inhibits performance. Athletes have been told to hydrate to avoid heat stroke but sometimes they overdo it.
For those who won't read the article... too much liquid intake can dilute the sodium levels in the body and lead to swelling of the brain which itself can cause all kinds of issues, some of which can lead to death.
Well, they used to treat diarrhoea by withholding fluids as an attempt to "starve it out", maybe it's something along those lines. E.g. it makes you heavier, you want to drink as little water as possible to stay light, or to minimise bathroom stops, or something like that.
Whenever I was doing intense physical effort drinking water made me feel sick. When I was a teen I didn't understand why so I assumed water is bad right after exercise. But later on I started reading on this and using some common sense and I started putting salts/minerals and some sugar in the water I was drinking and my body reacted completely differently. This was before sports drinks were a thing.
https://www.outsideonline.com/1900801/tim-noakes-serious-pro...