I have a Polar F4 with the chest transmitter. It's accurate when reading my heart rate, as I know how to do the ol' feel the pulse and count and it always matches what the monitor reads.

However, last night, I went to an hour of yoga (which was difficult for me, I've never been before and was definitely sweating buckets and can feel the soreness today), and then went to an hour of zumba, where I know I get an efficient cardio workout.

The monitor said I burned 927 calories. Does this seem ridiculously high, or can that be an accurate number??? It just seems way too high to me.

I haven't used my HRM in quite awhile, but when I did I usually burned about 400 cal per hour. So, for 2 hours=800 cal at a weight of 140ish.
So, yeah, you're probably about right. Good for you

That's similar to what the HRM I wore said I'd burn, also...400-700 an hour for moderate to intense activity. For me, though, those numbers bore no relation to the reality of what I actually burned. My HRM said I was buring 3500-4000 calories a day, I was eating 1800, and I consistently gained.

I think that sounds pretty accurate. I used to use the Bodybugg which would track my calories burned & when on the elliptical or running, I could easily burn anywhere from 10-14 calories a minute once I got my heartrate up. So lets say 45 mins in the zone = 450 calories for me.

And great job by the way! 2 hours of working out & 927 calories burned is totally kicking butt!

Thank you!!! I love classes, it makes it easy to go for two hours.