calories burned expirement: MFP vs Polar vs Body Bugg

CeleryStalker
CeleryStalker Posts: 665 Member
edited September 28 in Fitness and Exercise
So I went out on a bike ride today with my fiance, armed with both my Polar HRM and my Body Bugg. We cranked out a nice 18mph average over the course of an hour and sixteen minutes. When I got back, I plugged my data into MFP and synced my Bugg to the computer. Here are the results:

HR Max 85%
HR Average 77%
Duration: 1:16

Calories burned---
MFP: 1407
Polar: 787
Body Bugg: 487

Now it's well known that the BB is supposed to be within 5% accuracy when compared to the real deal testing you'd get at a human performance lab, because it takes into account so many more things than just your heart rate, age, weight, etc. But does it not seem WAY unreasonable that a 204#, 6' tall 35 year old female can exert herself with an AVERAGE of 77% her max heart rate for over an hour and only burn less than 500 calories?

I'll be doing the Polar/MFP/BB comparison test for the next several weeks as I ride, both on the tandem and on single bikes, and will post my results each time, but in the meantime, any insight as to what might be going on here is more than appreciated. Kind of hard to lose weight and eat back calories when you've got a range between 487 and 1407 calories! Even if I took the average of the three, I could be doing some serious damage!
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Replies

  • LoveLiveLift
    LoveLiveLift Posts: 459 Member
    bump This is an interesting experiment and I'm interested to see what you discover. I've been looking into getting a Body Bugg recently.
  • evandmegsmom
    evandmegsmom Posts: 88 Member
    Oh, that's so frustrating! No wonder there's no magic key to weight loss when we don't even know what to believe!
  • husker_gal
    husker_gal Posts: 462 Member
    I'm not sure how Body Bugg works but for your stats it looks like your Polar gave you the more believable calories burned count.
  • rmsrws
    rmsrws Posts: 639 Member
    I persoanlly figure about half of what MFP says for calories burned. But please keep posting as I am curious to find out your results!
  • kimberlyAjohnson
    kimberlyAjohnson Posts: 136 Member
    Definitely don't trust the MFP number. The body bug number looks really low!
  • taso42_DELETED
    taso42_DELETED Posts: 3,394 Member
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.
  • tukrainets
    tukrainets Posts: 119
    i have the polar ft7 and for my weight and height it seems to be right..but i agree... MFP database is WAYY off.. and the body bugg seems way to low!
  • gadgetgizzmo
    gadgetgizzmo Posts: 53
    Interesting. I too have been thinking about getting a body bugg so I look forward to seeing the results of your experiment.
  • Moonbeamlissie
    Moonbeamlissie Posts: 504 Member
    Very interesting!!!! I am interested in finding out more numbers!!
  • GaveUp
    GaveUp Posts: 308
    With polar you have to add age, weight, height and all the other stuff to. I just got a polar FT4... so now I wonder. I guess this is why we don't eat all of our calories back. Keep us posted.
  • withchaco
    withchaco Posts: 1,026 Member
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.
    Interesting... I wonder why this is? Makes me wonder if it's any good for other types of exercise.
  • KickassYas
    KickassYas Posts: 397 Member
    are you going to recommend testing these on other activities as well? cardio and strength? just curious.
  • Kath712
    Kath712 Posts: 1,263 Member
    i have the polar ft7 and for my weight and height it seems to be right..but i agree... MFP database is WAYY off.. and the body bugg seems way to low!

    Ditto!
  • Spayrroe
    Spayrroe Posts: 210 Member
    I was using the cal burn count for the machines at the gym and the MFP db for strength training. Then I got my HRM. Now, I noticed before that the MFP db wanted to give me about twice the amount of cals burned for a work out that the machines did (which, as stated before, is staggering when you're tracking your cals and told to eat back your exercise cals!!). Because of the huge discrepancies, I was avoiding eating back any of my exercise cals. My HRM usually gives me within 100 cals of what the machines said (elliptical machine gives me a higher burn count than the HRM, but the bikes give me a lower count than the HRM, but they're all pretty close), but my strength training was getting me a LOT more credit than the MFP db. Part of that could be because I try to super set when the gym is pretty empty (using one machine for a set, going to a second for my next set with the only break being while moving between machines, and then alternating back and forth till i get three sets on each), so I wasn't taking rest periods, so my heart rate stayed up more.

    In any case, I trust my HRM more than the machines and WAY more than the MFP db. It would tell me that I burned almost 1k cals after 45 mins on an elliptical, which seemed way too high to me.

    I am really interested to see how your study goes. I may have to do some research on this.
  • go2grrl
    go2grrl Posts: 190 Member
    I've heard folks have to wear their BodyBugg's on their legs to get a better reading during cycling. The lack of motion in the arms while on a bike might have something to do with it tho. But please keep us posted!
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.

    They had damn well better not tell me this. For what this thing costs, in addition to the $7 a month subscription fee, I want something that's accurate. BB is supposed to be the MOST accurate calorie tracker out there for consumer use. >=o(
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    With polar you have to add age, weight, height and all the other stuff to. I just got a polar FT4... so now I wonder. I guess this is why we don't eat all of our calories back. Keep us posted.

    Yes, my age, weight, height, resting heart rate, sex, all that stuff is loaded into my Polar. Mine even does a fitness test to get an idea of your V02 Max.
  • pyroxian
    pyroxian Posts: 99
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.

    Spot on. the BodyMedia product does not use heart rate for calorie estimation at all, it uses temperature, galvanic skin response (sweat) and motion sensors to estimate how many calories you're burning - when biking the vast majority of your motion is in the legs, while your arm (where the unit is attached) is very nearly stationary much of the time. You do see people using them on their legs cycling, but that is something that tech support @ BodyMedia don't advise, saying it will "confuse" the unit... *shrug*
    Polar HRM going to be your best bed for steady-state cardio, bodybugg/bodymedia fit are going to be closer for some things, and METs-based tables/estimators or VERY high dollar HRMs (Suunto T6D for example is $400) are best for strength training..

    anytime the topic of using an HRM to estimate calories burned comes up I always like to point people to Azdak's blog entries on the subject - this guy knows his stuff and has solid science behind his posts...
    http://www.myfitnesspal.com/blog/Azdak/view/the-real-facts-about-hrms-and-calories-what-you-need-to-know-before-purchasing-an-hrm-or-using-one-21472
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    I've heard folks have to wear their BodyBugg's on their legs to get a better reading during cycling. The lack of motion in the arms while on a bike might have something to do with it tho. But please keep us posted!

    I think you are dead on. My fiance was telling me tonight that because the BB has a cadence sensor for logging your steps each day, that perhaps the algorithm is messed up when cycling because you aren't bouncing all over the place, setting off the cadence sensor.

    It's just odd...even if the lack of cadence is throwing it off, it is still taking into account my age/weight/sex/heart rate/skin moisture/skin temp/how fast my body is releasing heat....it tracks a LOT of stuff to let just ONE thing throw it off so horribly.

    I'm going to be placing a couple calls to their tech support tomorrow. I say a couple, because you know how tech support goes....you usually don't get the same answer if you talk to more than one person.
  • tolygal
    tolygal Posts: 602 Member
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.
    Interesting... I wonder why this is? Makes me wonder if it's any good for other types of exercise.

    I think it's because part of the bodybugg's information comes from body motion. When riding bike (or other excercises that use mostly leg movement) your arms aren't going through the motion. I've heard of people wearing it on their legs too, but then it seems that you would miss some other factor. I'm not sure. My bodybugg seemed pretty accurate, but I was using it for running or elliptical.

    I can't wait to see the rest of your experiment. I was always curious, but didn't have a HRM to compare.
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    "it uses temperature, galvanic skin response (sweat) and motion sensors to estimate how many calories you're burning "


    That's interesting to know, and now that I look back over my activity manager, I see that it doesn't log HR at all. I wonder if I knew that at one point and just forgot it while the BB was hiding out lost in my house for 2 years, LMAO!

    Grumble. Maybe my next purchase is going to be a PowerTap. Why's it so damn hard to accurately estimate how many calories someone is burning? >=o(
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    ps...its good to know my polar is probably the most accurate....it's what i've been using the longest. :D
  • tolygal
    tolygal Posts: 602 Member
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.

    They had damn well better not tell me this. For what this thing costs, in addition to the $7 a month subscription fee, I want something that's accurate. BB is supposed to be the MOST accurate calorie tracker out there for consumer use. >=o(

    I think it is accurate - I always saw good results when I stayed on track. You have to remember how it works. If it can't measure something, it can't be that accurate. It's not going to be the best measurement for excercises where your arms are stationary.

    Here's how it works (from http://www.bodybugg.com/science_behind_bodybugg.php). On the bike, you're missing #1 because it can't tell that you're legs are doing most of the work.

    1.Accelerometer - The accelerometer in bodybugg® is a tri-axis micro-electro-mechanical sensor (MEMS) device that measures motion. This motion can be mapped to forces (g-force) exerted on the body. By taking gravity and motion into account along with the other sensor data, the wearer's body context and true level of physical exertion can be accurately predicted.

    2.Heat Flux - The bodybugg® also contains a proprietary heat flux sensor located on the side that measures the amount of heat being dissipated by the body via a thermally resistant material. In short, this sensor measures how much heat the wearer's body is giving off. Heat flux is an important parameter because the body tends to heat up the faster it burns calories.

    3.Galvanic Skin Response - Better known as GSR, this sensor is comprised of two "hypo-allergenic" stainless steel electrodes on the back of the armband that measure skin conductivity. Skin conductivity is how much an electrical current can pass between two points on the surface of the skin and is affected by sweat due to physical exertion as well as emotional stimuli such as psychological stress.

    4.Skin Temperature - Skin temperature is measured by using a highly accurate thermistor-based sensor located on the back of the bodybugg®. Looking at continuous measurement of skin temperature in conjunction with data collected from the other sensors can reveal the body's core temperature trends which are affected by the level of a person's physical exertion or lack thereof.

    The data these 4 sensors collect, in conjunction with the wearer's specific body parameters (age, gender, height, weight) enable the most accurate estimation of energy expenditure on the market today outside of a clinical setting.

    Hope that helps some!
  • kate2004rock
    kate2004rock Posts: 223 Member
    BUMP --- interesting experiment!

    As another poster said, I'd also be interested to know the variations between another form of excercise--even just a walk.
  • taso42_DELETED
    taso42_DELETED Posts: 3,394 Member
    I was advised by BodyMedia (same device as BodyBugg; different software) tech support that the device is not accurate for bike riding. In fact, they advised me to remove the device during bike rides, and just estimate the calories using an online calculator!! That's when I decided to send it back.

    I think the # on your polar is probably the closest to reality.

    They had damn well better not tell me this. For what this thing costs, in addition to the $7 a month subscription fee, I want something that's accurate. BB is supposed to be the MOST accurate calorie tracker out there for consumer use. >=o(

    Call them or hit up the tech support on their web site. I was pretty floored when they told me this.

    I think it pretty much is the best consumer calorie tracker out there, for "general life activities", but for certain things like weight training and bike riding, I think it has a margin of error, like anything else.
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    Sucks....I'll call them tomorrow. I've poked around on the web and have found multiple resources advising to wear it on the thigh, about 2" above the back of my knee. We shall see. The experiments shall continue! :)

    Thanks guys!
  • HeatherFeather10
    HeatherFeather10 Posts: 92
    Just wondering if you are wearing the Polar FT using a chest strap by your heart or on your wrist ? I have heard you won't get really accurate results unless you use the chest strap. I've got some links that I'll post later once I find them.
  • StuAblett
    StuAblett Posts: 1,141 Member
    I told you this was a worthwhile thread to start :bigsmile:

    I just got a Polar CS200cad unit for my bicycle, I'm really looking forward to seeing some much more accurate results, and being able to put them up online on a diary of sorts. :happy:

    Keep on testing and tell us the results please! :smile:
  • irenerose25
    irenerose25 Posts: 41 Member
    Very interesting. Will be cool to see how it works out!
  • CeleryStalker
    CeleryStalker Posts: 665 Member
    Just wondering if you are wearing the Polar FT using a chest strap by your heart or on your wrist ? I have heard you won't get really accurate results unless you use the chest strap. I've got some links that I'll post later once I find them.

    Chest strap. Do they make HRMs that go on the wrist? I'd never seen one!
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