Quote Originally Posted by Bike Chick View Post
Linda, I just caught this thread but wanted you to know that I have a Garmin 500 and I have been having the same issue. We time trial on Tuesday evenings and without the hrm the Garmin says I burn around 550 calories in a 10 mile hilly tt with an 18 mph average (which I think is close to accurate); with the hrm the Garmin says I burn 225--usually cuts it in half. DH has a Garmin Edge 305 and his heart rate records in the 500-600 range for the same tt. I think it has something to do with the Garmin 500.
THIS!!! The first few times that I used the 500, I actually forgot to wear the HRM. Yet the calorie burn that was calculated for those rides, was nearly double what it is on rides when I DO wear the HRM.

Linda