Notes
Was hoping to confirm that my higher AHRs this week was due to heat and heat acclimation "training" I've been doing. So instead of the 4 miler I had planned on at first, I ran the same 6 mile path as yesterday. Yesterday's run was in 77 degree temps at DP in the mid 60s as I wore a LS tech shirt, while today's run was in 72 degree temps, DP is mid 50s while wearing a singlet. I hoped to replicate the same sort of HR drift as I saw yesterday, where I stayed between 8:35 and 8:40 pace even as the HR climbed with every mile (149, 154, 157, 160, 161, 163).
It wasn't even close. Compared to yesterday, I was 7 seconds/mile faster in the first 3 miles (8:37 @ AHR 150 versus 8:44 @ AHR 153) and 41 seconds/mile faster in the last 3 miles (7:53 @ AHR 156 versus 8:34 @ AHR 161). My highest HR for any mile today was a 158 (last mile of run, 7:44 pace). Yesterday's mile 6 was an 8:32 @ AHR 163. Thought there was an increase in HR today (147, 149, 150, 156, 155, 158), this came with an increase in pace (8:51 first mile to 7:44 last mile).
I guess the lower temps, lower humidity, and different shirt made a huge difference today, so I'll stick with the heat acclimation training.