Notes
started off at 9:15 pace, then gradually increased to 8:41 pace by mile 4. Stayed at that pace til around mile 16 - 17, where legs started getting a little tired, and I started to get some heart rate drift, so slowed it down to 8:49 pace the rest of the way.
time in Z2: 23:00 (hr = 129)
time in Z3: 2:31:00 (hr = 142)