BodyMedia vs. HRM...HELP!

that is a very wide margin of error! from what i understand about bodymedia is that is measure body heat, which i suppose is supposed to be more accurate than the heartrate monitors that measure beats per min. i would trust the body media over the heartrate monitor burning a thousand cals in 35 mins is like a 35 min sprint, that just doesnt seem realistic from my knowledge of training. oh I'm sorry i just read the rest of your post about the other 45 mins I'm so sorry!! now that i have completely read your post i can see how your heartrate monitor gave you that reading. I, personally would still rely on the bodymedia unless it had a low batter or you were not wearing it properly.

I don't think that is true, the bodymedia device measures body heat so it would not matter where you wear it when cycling as long as your body heat changes, and that happens when you stand up from sitting or move to grab the tv remote

I would trust the HRM.

I didn't know Bodymedia measures body heat, but if that's how it works, I'd be burning 804893281409 calories a day due to my hot flashes and the fact that I will get hot and sweat from just walking up an escalator. :laugh:

I have an FT80 that has the ability to measure your VO2max. I'm sure it's a crude calculation, but if it's off, it make's a huge difference in your calculations. If yours has it, make sure you do the test properly and then make sure it's set in the settings. Also make sure basic height, sex, weight, and age are all set properly.

I wouldn't worry about subtracting your BMR. It's not that much for that hour.

I exercise almost the same amount as you did with the same types of exercises, and I regularly burn over 1,000 calories. The burn is also close to the that displayed on the machines.

I would stick with the HRM. I feel that based on the things I've read about differences in calorie calculation, the HRMs from Polar are probably your best bet.

My Bodymedia Fit usually reports more than my HRM during exercise, to varying degrees. My HRM is a Polar F7 that to my knowledge has no VO2 max test, and just computes it based on your age, weight, etc that you input. It does have a place to change it if you know what your VO2 Max is (I don't), and I know from experimenting with it that changing that number does dramatically affect the calories burned for a given heart rate. But I have it changed back to what its default was.

During a 45 minute TurboFire cardio session it will often show 700ish calories versus 450 on my HRM...I tend to believe the HRM more thinking that flailing my arms around as much as turbo fire does might make my BMF think there is more going on? I'm not sure.

On the treadmill, doing C25K one day my HRM showed almost exactly the same calories burned as my BMF. Another day my BMF shows 100 more (this is for a 30 minute run/jog session).

I walk the same 4 mile route often. It is quite hilly (there is about an 800 foot elevation gain/loss). I wore my HRM one day and it said I burned 550 calories. My BMF has ranged for this same route anywhere from 650 to 850. I have no idea which is right. It takes me 1:20 minutes to walk it and weigh 250 lbs.

At this point I'm afraid that the BMF overestimates my calories for exercise but I'm by no means certain. I think it will take a long time watching how the numbers play out as far as input/output vs. weight loss to see.

I realize these things can't be 100% accurate, but I still think it's crazy. These are exactly cheap items (okay, well not for me anyway!) How do I record my workout? Average the two?

they use different methods for estimating how hard you are working.

for around $4000 you can buy a breath analyser, which can tell by how much CO2 you are breathing out how much energy your body is converting (but you have to stay connected to it for around an hour afterwards to catch the co2 for the anaerobic work you did)

I don't think that is true, the bodymedia device measures body heat so it would not matter where you wear it when cycling as long as your body heat changes, and that happens when you stand up from sitting or move to grab the tv remote

Nah, it's very true. It measures heat, moisture, and movement. I have one.

just because you have one does not make that true, i have one as well, and i disagree.

Maybe you should read the manual, Madam Must Disagree.

Heart rate monitors don't give you accurate calories for strength training. http://www.sparkpeople.com/community/ask_the_experts.asp?q=75

Per the website: http://www.bodymedia.com/Support_Partner/BodyMedia-FIT-Armband-Advantage-Troubleshooting bodymedia should work for biking if you place it correctly, and my bodybugg gives me not unexpected numbers for biking. Not as high as I think I deserve, but people routinely overestimate burns, so I definitely just use it.

When I use my bodybugg and eat a 500 cal deficit off of that, I lose about a pound a week, so I pretty much trust its numbers. If you don't, average the two, or put in the bodybugg number and if you are still hungry, up it to the HRM number. I trust my body to tell me when I'm a dumbass and need to eat more.

i would trust ur HRM because it goes off of what ur body is say so it is more reliable..

I've had a BodyMedia Link for a week now, and while I am going to go with its estimates for a couple of months at least, I don't really trust it. Some observations:

* I have a standing desk at work and find it a little disconcerting to see that standing while working apparently burns calories at about the same rate as sleeping. Various online sources suggest that sleeping should be 1.0 METS and standing, 2.0 METS: BodyMedia gives me 0.9 to 1.0 for sleeping, 1.0 to 1.1 for standing, typing. (Today, it says 1.0 for both).

* If I stand while moving my arms a little more (I spent two hours yesterday standing at a table, sorting and pricing books for a charity bookfair), BodyMedia does give me 2.0 METS on average.

* Most of my exercise is riding my bike, and I find that though my cycling is usually vigorous by the "breath" rule of thumb (i.e. it's vigorous if you couldn't hold a conversation at the same time), it never shows as more than "moderate" according to BodyMedia. Online sources suggest that on average, cycling at the pace I do should be about 6.5 METS, but BodyMedia says it's 3.5 to 4.0. It's likely that my burn for cycling is less than it would be for most people, since cycling has been my main physical activity for many years and my body must be used to it -- but that still seems too low. People suggest putting it on your calf when cycling, but that seems certain to yield an over-estimate.

* Routine activity like sauntering down a hill while chatting with colleagues shows up as more energetic (higher METS) than cycling, and every time I walk up a short flight of stairs (without getting the slightest bit out of breath), it appears as "vigorous" activity.

* Cycling in the morning apparently consistently burns more than cycling at the same pace over the same route in the afternoon: I suspect this comes down to the heat flux measurement, as the air is about 15C here in the morning, but has been 35C in the afternoon.

* Despite all this (and despite cycling for 2 hours a day and standing for 9 hours a day), my daily total energy burn according to BodyMedia is only 10% lower than I had been estimating using the MyFitnessPal tools -- probably because it counts all those short walks about the office building that I wasn't counting before. And MyFitnessPal seems about right, going by my rate of weight loss.

I can only add, I find my bodymedia incredibly accurate. Having said that, I don't bike. Why not give them a call and see what they say about biking, and the suggestion to wear it on your leg.

Their official advice is to wear it as normal when on a road bike. They acknowledge that it is more accurate for some activities than others, but say that for most people, it should average out to 90% accurate across all your activities for the day.

The HRM will obviously be the best sensor for determinig caloric expenditure, however it is not the sensor that calculate caloric burn, but the software that is used with it. There are big differences and you will notice it if you use Polar H7 HRM with 2 different iPhone apps running at the same time. I noticed a 20% difference for the exact same acticvity (I had several apps logging the same activity at the same time). This is becuase the algorithms are generally different in each app. Also you have to remember to subtract your Basal Metabolic Rate, but that is the same with all the apps I know of.

Bodymedia is a toy and I have never seen it used in any independent peer review academic/medical study. Always go with the HRM.