Notes
86F 55%H 68DP, at the Alpharetta Big Creek Greenway. Did 3wu+8MP+3cd. Wore both the 310xt and 910xt. The 910xt showed 0.16 miles less distance than the 310xt. That has an affect over 16 miles of 11 seconds per mile. This just confirms my suspicion regarding the two GPS chips in them. The cd miles totally kicked my butt. The MP miles got hard but they were doable. I don't know that I believe that I slowed as much as is shown.
My averages for the MP miles were: 10:12 (I'm sure I was faster), HR 129 (and gradually going up) Cadence shows 178; I was using metronome 175 which seemed OK for this pace. A temperature of 86 has a heat offset of 0:27 seconds = a 10:17 (from 9:50 target MP) pace. I was actually trying for below 10:15, so I did hit my target pace