It was an enjoyable 7-mile run. It was the first time I'd run that far since June, although I'd done several longer, more intense workouts in the intervening months.
That's why I couldn't figure out why I felt so horrible all day. If seven miles does this to me, then what are 26.2 of them going to do. Later that night I threw up. Two of my five children threw up. The three children staying with us because their parents are enjoying a cruise while we clean up their kids' puke threw up.
Turns out that running is...contagious.