After tending my three-year-old grandson for three hours, I ran two miles on the Jordan River Parkway. It was 92 (F) when I returned, and I was ready for some liquid. I drank a glass of water just before I left, and by the time I reached the one-mile turn around point, I was thirsty. Because of the short length of the run, I didn't take liquid with me. I normally would have run the two miles on Tuesday, but because I didn't run on Monday, I shifted my Monday run to Tuesday and my Tuesday run to Thursday.
My wakeup HR was 47 and I felt pretty good this morning.
Sports scientists used to say that it was best to drink liquid before one became thirsty, but they now say it is best to wait until one is thirsty. By doing that, one reduces the likelihood of over hydrating and thus having electrolyte levels that are too low. Over hydrating is as dangerous as under hydrating because of the dilution of the electrolytes due to excessive water.