Set my PR for hottest commute yesterday. I saturated with water beforehand and felt fresh. Was fine at first then after 20 miles or so I felt inexplicably crappy. Then I realized, now might be the appropriate time to have a sports drink on hand. I've always shunned them because of the ridiculous amount of sugar, and the fact that you are usually more likely to see a NASCAR fan or chubby kid in an arcade drinking one than a serious athlete. But OK, 36 miles in 105+F heat index, I could see maybe having a little something extra. So long as I still have good ole H2O to dump on my head.