HRM calories burned vs. GYM machine readings

Pkiddy

Advice from Polar FT7 users... i have this HRM. when i wear it it talks to the machines at the gym. i'm finding that regarding calories burned, i'm getting different answers even though the HRM and the machine have my age and weight programmed. the elliptical comes in higher and the tread mill lower than what the HRM says.
and it's not a small difference - it's quite a bit of one. example, on the elliptical, say for 60 minutes, the HRM will say 320 calories and the machine will say 600! the machine has the advantage of knowing incline and resistance even. which should i go with?
anyone know why such a dramatic difference?
Thanks all for your help/comments, etc.!

busyPK

I have a Polar FT4 and it also can sync with my workout equipment and I also find a difference, but not as much as you are saying! That is nuts! My guess is the machine isn't taking into account your height? I don't have any other idea though, but I'd go with what your HRM says.

Pkiddy

@kmtcm4 - it's probably that. i'm only 5'2"... maybe the machine is based on Avg height. Thanks! I hadn't thought of that

TNGirlyGirl

If there's a discrepancy, go with the HRM... it's using YOUR numbers, not some "program" to take an educated guess!!