I have a question about my heart-rate monitor counting calories.. I'm a little confused by it all.. Apparently it judges how many calories you've burned by your age/height/weight and heart-rate.

Now, my question is, don't different ACTIVITIES at different heart rates burn more or less calories? (Running vs. climbing stairs) Or is calorie burning just a matter of how 'worked-up' you get? (and of course, how long you maintain it)

Thanks for any and all replies!

No matter what the activity is, the number of calories you burn is determined by your heart rate. So let's say your HR monitor is reading 150 ... it doesn't matter if it got there by running, elliptical, swimming, biking or lifting weights etc. It's all going to be the same number of calories burned.

This is one of the reasons why we should ignore the calorie readouts on cardio machines. Every manufacturer wants us to believe that we're burning more calories on *their* machine than someone else's, so they give wildly inflated calories per minute burned. In reality, it's all based on our HR, regardless of the equipment used.

Hope that helps!

Yes I can see how it is confusing. The higher your heart rate, the more calories you burn, but if you believe in the heart rate training as set by Polar/Sally Edwards, you can get above your aerobic zone and burn glucose\lactic acid for fuel (another subject)

But you can have different levels of fitness on each machine/exercise

My heart rate is lowest on a treadmill slow walking/
My heart rate is in the medium to high on the elliptical, same as the exercise bike.

It will make sense once you keep track of it for a while.. then when you need to up your intensity you'll know exactly how much harder you'll need to push yourself... go up a few on the resistance, etc.. you'll be able to go in and out of your heart rate zones pretty easily if you pay attention to it.

Thanks for the responses! I was fairly sure it was based on HR, but there seems to be a lot of conflicting info. out there, and I was confused with those 'calories per hour' charts for activities..

I just got one of the Polar F6 heart-rate monitors for Christmas and it's my new toy.. I love it. A few years ago when I had a personal trainer (that didn't really work out for whatever reason), I had used a heart-rate monitor but the strap made me nutso.. I had thought of getting a MIO, but they don't have continuous measurement which wouldn't be good for running or other aerobic activities.

I got my Polar after being convinced by the attendant on the sales floor that Nike was more form than function, and that Polar had a better reputation. After getting my HR monitor home and setting it up, I was quite pleased with the comfort and fit of the HR monitor strap. It was a LOT more flexible than I remember even though I'm bigger now than I was. The old one used to dig into me and bother the HECK out of me!

What's this thing with lactic acid though? Is that if you're continually over your max target zone?

Thanks again for any responses!

I love my Polar F6 too!

The "calories per hour" charts are all based on guesstimates of exercise intensity -- in other words, your heart rate. It's far more accurate to wear a HR monitor and actually KNOW what your heart rate is, rather than relying on a chart based on averages that might have nothing to do with you or your fitness level.

Interesting, once I started wearing a HR monitor, I learned that my highest recorded heart rate ever was lifting weights, not doing cardio, and that weightlifting can be cardio if you keep your rests short. Since I like lifting weights much more than cardio, I'm a happy camper! (but I do my cardio every day like a good girl anyway)

The lactic acid is if you are in a very high zone (I think 90%) so I wouldn't be too concerned. I have the F11, I just got it, it's pretty neat.

Does anyone know how this stuff is impacted by body fat percentage? I got a HRM for Christmas too and I'm excited about it, but I remember my old spinning instructor telling us that we should all lift weights because a pound of muscle burns more calories doing ANY activity than a pound of fat, which essentially burns none. So, I wonder if there is some standard BF% that HRMs assume. Has anyone ever heard anything about that?

I've never heard of a HR formula that takes BF% into account. It's an interesting question, but I think any difference based on lean body mass would be fairly negligble. We have to remember that even HR monitors are only giving us averages and guesses on calories burned. They measure your heart rate, but are applying a formula based on age, height, weight, and sex to give you calories burned. Any of our individual stats could be different from the formula. The only way to truly accurately measure calories burned would be in a lab, hooked up to breathing equipment measuring O2 consumption. And that's just not very practical for most of us!

As far as the BF%, I would think that it ESTIMATES it from the height/weight/age calculation.. Not 100% accurate, but it probably knows there's a higher BF% for someone say, like myself, 5'4", 216 at 24y.o., as opposed to someone who is say at my ideal, 5'4" 128 at 24y.o., but again, that's just a guess and maybe why they need the height/weight/age??

Eh.. THEN AGAIN, that can variate SOOO much. The first time I got down to a "normal" weight (128lbs), I basically starved myself and lost a lot of muscle from not working out, so I probably looked about 150lbs or so.. Definitely not a healthy 128. I was probably all FLAB.. I'm curious about that too. Anyone have any luck with those body-fat percentage scales? I HATE calipers.. Ouch! (I just have a standard scale, myself!)

Does anyone know what the formula is to calculate calories burned?

Today when I exercised my Polar F6 HRM said I burned 213 calories with an average heart rate of 142. But when I entered the exercise into fitday, it said I only burned around 75 calories.

Jen, I would always use what your HR monitor says over Fitday. Your monitor is actually measuring your exercise intensity (your heart rate), while Fitday is only a wild guess that doesn't consider any personal data such as gender, age, weight etc.

As a general rule, Fitday's exercise estimates are notoriously inaccurate and many people ignore that part of Fitday entirely (including me, though I love the food tracker). I think you're going to get a far more accurate idea of calories burned with your HR monitor.

Thanks Meg. That makes me happy to hear. I exercised for a little over an hour today and my HRM said I burned 637 calories. Yippee!

BTW Meg, I checked out the links in your siggy and your story is so inspiring! Thanks for sharing it.

Thanks everyone for the information! I'm really excited about getting a heart rate monitor! i did loads of reading and research and have settled on getting the polar F7female. i cant wait to get it! going to order it tonight