I did a 38mile ride with 3000ft of climbing, my calories used was just 790 yet the rest of the group I was with all used around 1600 calories, how is this calculated, I've noticed with my commute some days I can have used a couple of hundred calories others considerably less for the same route. don't use a power meter just hr and cadence.
This doesn't really answer your question, but it is generally agreed in cycling forums that Garmins and other bike computers tend to massively over-estimate calories burned during activities.
Most using garmin, 4 all use 520 edge same as me. Every one else burned in excess of 1600 calories I burnt just 790. Went out on commute today, 12 miles relatively flat and yet burnt over 500. Don't mind it being inaccurate just looking to understand why it's so inconsistent
Yeah I agree. The absolute values don't much matter as long as they are consistent. Same with the Index scales. I'm sure the fat % isn't spot on but it does allow you to see trends up and down.
Is your weight logged correctly in the garmin connect App? That's the only obvious thing I can think of that might make a big difference.
I have found that using a heart rate monitor with a chest strap increases the accuracy of the calories burned, not only should the weight be correct in the app it also should be correct on the Garmin device itself along with age and height.