Charge 2 calorie burn accuracy

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kayla_who
kayla_who Posts: 540 Member
Hi. I've had the flex for 3 years and just now upgraded to the charge 2. I've read that the ones that monitor heart rate are more accurate for calorie burn. However it is giving me way more exercise calories than I would have expected. The heart rate monitor is accurate and consistent. I'm just not sure about the calorie burn part. Should I trust it?

Thanks

Replies

  • SusanMFindlay
    SusanMFindlay Posts: 1,804 Member
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    Were you losing faster than expected with the Flex? If you weren't and the Charge 2 is telling you that you're burning more calories than the Flex did, then don't trust the Charge 2 numbers.

    My Charge 2 numbers are great, but it seems to depend on what type of exercise you do and on the ratio of "working out" to "just being active as part of life".
  • cordney
    cordney Posts: 73 Member
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    I believe my calories are wildly inaccurate. My workout today I used the chest strap hrm from my treadmill and wore my charge 2. Treadmill said 506 calories and charge 2 said 809.
  • Francl27
    Francl27 Posts: 26,372 Member
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    My calorie burns seem on the low side actually. I think it will depend a lot on what you do with the hand you have it on too.
    cordney wrote: »
    I believe my calories are wildly inaccurate. My workout today I used the chest strap hrm from my treadmill and wore my charge 2. Treadmill said 506 calories and charge 2 said 809.

    I'd double check your profile information to make sure it's accurate, that seems very odd. What kind of treadmill workout was it?
  • PenJane16
    PenJane16 Posts: 3 Member
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    Cordney, did you see the article on the MFP Blog site that says calories burned on treadmills etc. are LESS likely to be accurate than wearable trackers? It makes for an interesting read! :smile:

    cordney wrote: »
    I believe my calories are wildly inaccurate. My workout today I used the chest strap hrm from my treadmill and wore my charge 2. Treadmill said 506 calories and charge 2 said 809.
  • PenJane16
    PenJane16 Posts: 3 Member
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    kayla_who wrote: »
    Hi. I've had the flex for 3 years and just now upgraded to the charge 2. I've read that the ones that monitor heart rate are more accurate for calorie burn. However it is giving me way more exercise calories than I would have expected. The heart rate monitor is accurate and consistent. I'm just not sure about the calorie burn part. Should I trust it?

    Thanks

    I'd go with it! :wink:
  • PenJane16
    PenJane16 Posts: 3 Member
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    cordney wrote: »
    I believe my calories are wildly inaccurate. My workout today I used the chest strap hrm from my treadmill and wore my charge 2. Treadmill said 506 calories and charge 2 said 809.

    Just worked out how to reply to a post! Please see my answer below (or above, as the case may be!) :wink:
  • stk_pkr
    stk_pkr Posts: 18 Member
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    I'm in maintain mode and the Charge 2 vs my Charge is reporting 2x as many calories for the same level of activity. Also, it seems my steps are lower on the Charge 2 vs the Charge.
  • heybales
    heybales Posts: 18,842 Member
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    cordney wrote: »
    I believe my calories are wildly inaccurate. My workout today I used the chest strap hrm from my treadmill and wore my charge 2. Treadmill said 506 calories and charge 2 said 809.

    Would have been more interesting to know what the avgHR was seen by both. Or if chest strap was reporting to phone which was used by Charge 2 also - answer that question.

    First, the treadmill is NOT likely to be using HR to calculate a calorie burn, rather merely display the stat. Unless it asked for gender, age, weight, and height as a minimal to start with, there's not enough stats from just HR to estimate calorie burn. If it was truly doing that - it's worthless treadmill function.

    Likely it was doing pace based as almost any other treadmill - which can actually be more accurate than HRM by potentially a long shot.
    Depending of course on the accuracy of the treadmill calibration - it must know the pace correctly, and you must enter weight correctly.

    http://community.myfitnesspal.com/en/discussion/774337/how-to-test-hrm-for-how-accurate-calorie-burn-is/p1

    Treadmills have been used for ages longer for research than HRM's even have been - and formula's for getting accurate calorie burn have been researched out the whazoo.

    Also - your device takes at least a week, perhaps 2, to start learning you - to apply better formula for the calorie burn based on what it sees.
    It needs an avg resting HR (so if elevated from meds or disease - forget a good estimate), and accurate high end HR reading (so if it's erractic or stops at some point - forgot a good estimate on more intense stuff).

    You can double check which seems more likely using this calculation, and select Gross, since that's what everything else would be using (database, Fitbit, treadmill, ect).

    http://www.exrx.net/Calculators/WalkRunMETs.html

  • heybales
    heybales Posts: 18,842 Member
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    kayla_who wrote: »
    Hi. I've had the flex for 3 years and just now upgraded to the charge 2. I've read that the ones that monitor heart rate are more accurate for calorie burn. However it is giving me way more exercise calories than I would have expected. The heart rate monitor is accurate and consistent. I'm just not sure about the calorie burn part. Should I trust it?

    Thanks

    Only asking because many people are confused and think their MFP calorie adjustments are exercise calories - when it's not.

    So you mean literally for an Activity Record that you view in your Fitbit activities, same workout, is a big difference between devices?

    If you do mean the MFP adjustment - your daily life could be more active than prior device saw - or new device is still learning you, and it sees elevated HR and things exercise, not realizing yet you always have a high resting HR perhaps.

    You never said what the workout was, which has a huge bearing.

    HRM is terribly inaccurate for anything calorie burn related except what those formulas are designed for - steady-state (same HR for 2-4 min) aerobic exercise.
    The farther you move away from that (like the opposite lifting or intervals anaerobic) the more inaccurate that formula using HR is.
    Manual logging is better then if you spend a lot of time doing it.

    Just to confirm - you know the HRM readings are accurate and consistent by what comparison?
  • cordney
    cordney Posts: 73 Member
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    Francl27 wrote: »
    My calorie burns seem on the low side actually. I think it will depend a lot on what you do with the hand you have it on too.
    cordney wrote: »
    I believe my calories are wildly inaccurate. My workout today I used the chest strap hrm from my treadmill and wore my charge 2. Treadmill said 506 calories and charge 2 said 809.

    I'd double check your profile information to make sure it's accurate, that seems very odd. What kind of treadmill workout was it?

    Everything is updated on the Fitbit and the treadmill. I was just walking at an incline.
  • acole5690
    acole5690 Posts: 17 Member
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    Well I've only had my charge 2 for about 3 months, my calories from just steps i think is accurate when it syncs to MVP because of the calorie adjustment. But i do burn more calories when i'm doing a workout so I think it is accurate, it measures the highest of your HR to determine how many calories you burned. Like i did a step class and zumba class back to back, my average HR was 200 and i burned about 1100 calories for 95 minutes
  • heybales
    heybales Posts: 18,842 Member
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    It reported that your average HR, for that entire time span - was 200?

    That is so incredible as to be incredulous - and doubtful.

    Not because of your potential fitness level and ability to push it for so long and hard at exercise is at question.

    But because the ability to have the device measure that high for so long a HR is doubtful.

    Now actually, depending on other stats - 1100 calorie for 95 min is very doable.

    Merely that ability to measure that high. Most people report the device gets more inaccurate for HR readings the higher they go, so report at certain point it just blanks out and reports nothing on it's way up.
    And not talking high numbers either - usually seen around 140 to 160.