I felt kinda wiped and a hair light-headed after I was done, but a few minutes of rest (sitting on a flat bench and stretching gently) took care of it. By the time I left the gym, I felt fine.
My last run was last Tuesday. I was going to run Thursday, but as I was walking through the city after dinner I turned my ankle on an uneven sidewalk. It wasn't horribly injured, though it did wind up being just a tiny bit swollen, but I decided it was better to give it a bit of a rest than to maybe make it worse by running on it.
The following are largely for my own records: I lose about 12 ounces of water during a run. (Method: weigh self before running, on scale at gym that measures tenths of pounds and gives consistent results. Drink 16 ounces of water during and immediately after the run. Weigh self after the run, do math.) Max heart rate is about 147, which is pretty much at the top of the range of where I should be exercising. The treadmill claims that my workout burns about 315 calories.