The coach won’t be giving them salt directly, but will always provide a sports drink which contains salts.
Ever watch any sport and a player falls over with a cramp? They have drunk too much water and not enough electrolytes.
Here’s a study from one hospital in Oslo, Norway. Norway is not considered a hot region of the world. Between 2010 and 2015 they treated 31,000 patients in the ER from a population of 135,000 for electrolyte imbalance. That’s roughly 18 patients a day. This is not some sort of fringe case.