Went out on a ride today, bike has an Edge 520. I also have a fenix 5X. As an experiment I used both devices to record the activity. I forgot my HR strap, so the Edge 520 did not get HR information. The fenix 5 used the optical HR. There is no power meter on this bike. There is a cadence, which fed to both Edge and Fenix. The stats are very comparable, with one glaring exception. Time was 1:33:55 vs. 1:33:53. Average speed was 18.3 mph. Elevation gain was 804 vs. 853. All well within margin of expected error. However, within Garmin Connect the Edge 520 shows calories as 2,202, whereas the fenix shows 1,228. Both of these uploaded to Garmin Connect so I assume the same athlete specs are being used. Any idea as to why there is such a vast difference in calculated calorie burn? The only obvious difference is that the fenix had HR information, but I don't know how that is used in the calorie calculation.
