I have noticed that it is much harder to get calories burned on outside walk and even for that matter exercise minutes. I also notice that when you reset the activity tracking and recalibrate it they are much closer in the beginning but the indoor always burns more calories after a few weeks again. Does anyone else notice this? I would love to know which one is more accurate? I would also state the intensity of my walks are the same at about 3-4 mph and I really get drastic differences.