This damned watch!!

nurseygirl66

So, I'm running a 5k soon. I'm 5'10, 190 pounds and I've been training outside and on the treadmill. I've read everywhere that you can't rely on the calories posted on the treadmill as you excercise. So, I bought a watch that can check heartrate, and you can enter your age (not wt) and it has a feature that counts cals based on your heartrate. The treadmill told me 521 cals for 46 minutes at approx 4.8mph. The stupid watch told me over 650 cals for the same period of time, and it's well over 1000 cals now, after I ran, and have rested for about an hour- not sat, but doing a few things around the house. Which can I believe, or not??