Budybugg VS HRM

MisdemeanorM

I have both.

On non active days I typically burn just about 1800 calories. This is just a plain old sit at my desk day. No cleaning, grocery shopping, etc.

I've noticed that it's been telling me on days like yesterday - where I did 45 minutes of spin and 20 minutes of walking (HR about 155/160 avg for spin and about 115/120 for walking) that I burned an extra 250 TOTAL calories. My HRM told me I burned about 500 in spin and about 125 walking (which was right after spin). Even with backing out some calories that would already be counted, that is a pretty big discrepancy between the two of them. My HRM tells me about 200-300 more than my BodyBugg (I actually have a BodyMediaFit, but it and BodyBugg are exactly the same thing now).

I'd lean toward the Bodybugg being more accurate - but I also don't see how an hour of cardio can be only 250 calories? Being preg, I'm not pushing myself as hard as I would in the past, but my HR is still up between 150 and 175 the majority of the 45 mins, in spin at least. Is that just a "false" HR / burn rate when you're pregnant? I have to say, working out so much for barely any burn is getting old and frustrating!

mrssturgeon7911

I got sooooo sick of my bodybugg, I even had the wrist thing that i could check all day. It's expensive too keep getting the subscription *Had bodybugg for 2 years* I got a polar HRM from DH for birthday and I feel like it may be way more accurate but that is just my opinion. It tells you what your heart rate is at that moment so that's why i feel that way. I guess I also just don't feel that my bodybugg kept up very well..haha

pilotgirl2007

How does the body bug determine how many calories you are burning? Is there a HRM function to it? I would be more inclined to say that I would trust the HRM more than something that isn't using your heart rate to determine calorie burn. Thats just my opinion...

MisdemeanorM

Here is what they say. It just seems SO off. I suppose once I am not preg and trying to lose I might be able to tell it's accuracy better than I can right now.

I hardly ever sweat though. Even at hard exercise. I wonder if that makes the calorie burn less accurate on me personally? Though it seems to get the "time exercising" pretty accurate - though I was surprised to find that even my hardest workouts are considered "moderate" activity not "vigorous" activity in their default settings. And this is getting my HR up to 85-90%...

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http://www.bodymedia.com/Professionals/The-Science

The Science
Your BodyMedia® FIT Armband has multiple sensors. Those innovative sensors take 5 different “views” of your life:
Motion The Armband contains an accelerometer, a device that measures motion. (Your car air bag has an accelerometer in it that lets it know when you've been in an accident.) We use it to measure HOW you move from multiple axis and perspectives, allowing us to better understand your activity.
Steps We count your steps, using the accelerometer to measure the distinct patterns created by walking and/or running.
Galvanic Skin Response When you sweat, your skin becomes more electrically conductive. This measurement help us see how active you are.
Skin Temperature There's an electronic thermometer inside your armband that helps us know how hot you are.
Heat Flux When you move, your muscles produce heat. We measure the heat that's flowing from your body into the environment.
Once we've gotten these “readings” we can determine what kind of exercise you're getting, and how difficult it is for you. That's important since your body burns calories differently than anyone else's.
Our clinically proven algorithms crunch your numbers – pairing up sensor data with calorie information and presenting it to you via the BodyMedia FIT Activity Manager… so you know how far you are toward reaching your goals!


BodyMedia FIT is Clinically Proven to be Accurate

The BodyMedia FIT System has been Clinically Proven to Accurately Measure the Amount of Physical Activity and Calories
A recent independent study tested our Armband system in real-life situations. Participants engaged in "free living" activities, including brisk walking, running, bicycling, sedentary activities, home activities, home repair, occupational activities, strength training, and ball games. The study compared the armband to a $40,000 "portable oxygen analyzer", the gold standard for measuring calories. Results showed:
Total Calories for free living activities: mean error <10%.
Total Minutes of exercise: mean error <5%.
Source: British Journal of Sports Medicine. July 2008.

pilotgirl2007

I don't know, I personally think that your heart rate is a more accurate way of measuring how hard you are working your body and not how much sweat you are producing and how hot your temp is. I did a quick search to see if I could find a study on the body bugg that has been published but I didn't see anything. I am really curious to see what any studies that were done have to say about it.

And what exactly constitutes a "free living activity" because 10% off on your total calorie burn for an entire day could be quite a bit. And that is the mean discrepency meaning that there were people who could have experienced more or less than the 10% that they are claiming.

MisdemeanorM

I think my HRM has to be more accurate - just based on this - Yesterday, I went to SPIN class - 50 minutes avg heart rate about 150/160. It says I burned 230 calories. After spin I walked a mile (20 mins) avg heart rate around 115. It says in that 20 minutes I burned 150 calories. There is no way that in 30 extra mins of high cardio I burned only 80 more calories than a leisurely walk. I imagine that the band is accurate for sitting around and base rates, but it seems to be highly off for cardio. This is not my first surprise that my cardio burn is showing as less than I would expect it to be - and way less than my Polar HRM tells it to be.