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.
That’s a very incorrect statement. NaCl, KCl, and MgCl2 are essential for our bodies to function appropriately. If you are working out for an hour or mowing the lawn on a hot day, you are mostly correct. You can replace the lost salt though a balanced diet. If you have sustained sweating, such as when you run a marathon or play a match of football, it can be deadly to not replace these salts.
Shouldn’t be a problem to tie them both together. You’ll want to add check valves on both lines before they join together. If you haven’t bought a fan yet, I highly recommend the Panasonic WhisperFit series. They pull a ton of air, are energy efficient, and are very quiet. I went from having condensation on my mirror after a shower to nothing at all.