It seems like you talk about sweating - thats why you talk about the replenish water and ectrolytes part. I hope you know how sweating works and that it only works if the humidity is not too high.
So what do you think happens if the air temperature is over your body temperature and sweating dies not cool you down?
Maybe you should read a book. I am really curious about a biology text book that will tell me that 40C and 100% humidity is totally fine for humans for survive, lol.