I also do not agree with the study done on exercise. Personally, even strenuous bike riding in the summer heat can wipe me out where I am lethargic, dizzy, pale, no energy, and sick to my stomach. I always make sure to have extra on hand when hiking (and almost always need it for anything longer than 5 miles  - or with an elevation gain of over 1000 ft. - less if it’s hot).

I am not a saltwaster - in fact extra salt makes me blow up like a balloon and makes me dizzy.

Susan A.