Didn't feel much like doing it, but I went for a 5 mile run anyway this evening after work. Once I got a couple miles down the road I felt a lot better about the idea, and of course by the time I finished I was really glad I got it in.
For some reason, I picked a hilly course, which in the heat made it all the more difficult. But I was going pretty slowly, so it really didn't matter. No matter how fast you do hills, they always speed up the process of getting in shape.
So, I logged 5.1 miles in 49:18, which is a 9:40 average.