That sums up yesterday's run. It had been a few days since I last ran, so I wanted to get some miles in by doing an LSD around the Back Bay. Knowing it was going to be a warm day, I started a little after 7:30 AM. As I would find out later on, that was not early enough!
Overall the run was a normal run around the bay. At mile 6, I felt pretty good. My heart rate was right in line. Speed was slow, but still not bad (10:15 or so). Everything was going fine until about mile 9. The sun was blazing and started taking its toll on me. Slowly, my heart rate had been creeping up. I had been slowing down to compensate. I had been successful, but I was finding myself slowing into the 12 minute per mile range to try to keep my heart rate down in the target range.
I kept slowing and slowing and slowing. By mile 11 I was at a brisk walk and was having trouble keeping my heart rate below 85%MHR. I tried to hydrate to see if that was going to have any affect, but it was too little way too late. Physically I still felt fine, so I picked up my pace to jog and finished the last uphill push to the car at CDM. When I got back, my thermometer in the car was showing 76 degrees - and it was only 9:30! Stats for this run - 12 miles, 2:20.19 (includes a couple of stops) and overall 81% MHR.