Okay this heart rate calculating is getting to me. I started the 50 mile training plan and at the start the average heart rate for the 1 mile test was 172 and I used that to base my heart rate zones in my Garmin watch. 8 weeks later and I did the 1 mile test again and the average heart rate is 183. This confuses me, shouldn't it be lower than the first time? Granted I did run the 1 mile quicker t…