The weather problem at a school meet is a standing-around problem, and logistics solve it.
Fluid on a schedule, not on thirst
A bottle on the bus, one across the morning, one finished 60-90 min out.
Salt comes from the pretzels and crackers already in the cooler.
The cooler stops being optional
Perishables get two hours between 40F and 140F, and one hour above 90F.
The sandwich that was fine at 8am is a different item by noon.
Thirst disappears, fluid loss does not
Cold drives blood inward, which raises urine output and blunts thirst.
They finish down on fluid having never once felt thirsty.
Warm fluid is what gets drunk
A thermos beats a cold bottle that sits untouched in a bag all morning.
Bars freeze, bananas turn to mush, and gloves do not open wrappers.