Having seen it in my students when I was teaching diving and not recognizing it in my self on a hot day in my garage, I'm embarrassed to admit I ended up in an emergency room with heat exhaustion but it can really sneak up on you. That made me remember that when we went out on conditioning hikes in the Marine Corps the Navy Corpsmen would halt us after about an hour and give us all a salt tablet and force us to take it with water. It makes sense, you sweat salt water, and my solution now a days is to add healthy pinch of finely ground Himalayan salt to a liter of water. It doesn't affect the taste that much and it replaces a lot of what you're losing while toiling in your garden on a hot day. For what it's worth, at 79 years old, my cardiologist approved. Hope it helps, Hank
