HRM Margin of Error

abbeyjones1994

I received a Polar FT7 for Christmas, and I love it. I use it for my walking, running, and elliptical workouts.

I have heard that, although seemingly more accurate than the MFP database, HRM's can overestimate calorie burns by as much as 20%. Since I read that, I have been manually entering my exercise on MFP as whatever my HRM tells me I burned -20%. If I'm doing this, do you think it's safe to assume I have covered any margin of error and can more than likely eat the calories I recorded back? Or is that too much/too little room for error? I'm down to my last 8 pounds and set to lose 0.5/week, so I know any misestimations can screw me over for the day.

Also, I don't know if stats matter at all in this situation, but I'm 20 years old, 5'2", 123 lbs, aiming for 115.

MeanderingMammal

abbeyjones1994 wrote: »

HRM's can overestimate calorie burns by as much as 20%.

If you're using it as it's designed to be used, for steady state aerobic range CV work, then it's potentially in the 10% either way range. So that would be for distance running, rowing, cycling. When you're using it for walking it could be in the realms of 40% out, more likely high, as your HR is unlikely to be in a range where it's a reliable indicator of calories expended.

If you do any form of interval training then the error could be anything from 10%-50% high.

athena61

You'll know soon enough and can adjust accordingly. I record my calories as is (FT60) and am losing anywhere from .5-1.0 per week. Just pick a percentage and go for it.