I could tell before I left for my run that I was tired. First, my wakeup HR went from 48 to 53. Second, I didn't feel energetic, just a tired feeling. When I started running, I quickly had confirmation that I was tired. So, after 15 minutes I turned around and headed back. My pace varied from about 11:15 to 12:15, and I did 2.36 slow miles.
I'm running about a minute/mile faster than I was before the SLC half marathon to get my body used to a 10:30 pace as my recovery/rest pace, and I'm not surprised that my body needs a break. Also, I've only gotten 6 hours sleep/night for the past few nights, and that takes its toll, too. It will be interesting to see how I feel tomorrow.