Notes
Got some kind of weird leg cramp. My left shin felt tight and it seemed like my left foot was slapping the pavement. But it sort of felt like there was tightness in my hamstring responsible, like it was making my foot pivot and hit the pavement wrong. Overall I was definitely hitting the ground too hard; my usually quiet footsteps were loud. Twice (or was it three times?) I had to stop and take walking breaks to loosen it up. I thought I was going to have to walk or possibly even take the bus home. But in the end I was able to finish, right on pace (which tells me I was running too fast because the two walk breaks should have pushed my time up closer to 12 minute miles). The scary thing was at one point the stiffness in my left leg felt like it was pulling on my knee. By the end of the run, the leg had loosened up considerably and wasn't too bad at all. But this was unpleasant and I need to try to avoid it in the future.
One thing: it felt like my shoe was laced too tightly at the start. Not sure if this can really make a difference but worth keeping an eye on. Also, I had a lot of coffee the last two days; maybe dehydrated? Finally, I started using that stretching machine again at my work gym. I had some problems before when I was using it; maybe I shouldn't.
Anyway, kind of a good HTFU in that I was able to keep going and loosen it up. But better to avoid this altogether in the future.