Established Fitbit charge hr users

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Replies

  • d_thomas02
    d_thomas02 Posts: 9,055 Member
    edited January 2016
    My charge HR was incredibly inaccurate in the first few days, but it is close to spot on now. Is the Fitbit burn estimate throughout the day the TDEE?

    TDEE is Total Daily Energy Expenditure. The FitBit displays your current calorie burn, that is the number of calories you have burned so far in the day. If you look at FitBit's estimate of the calories you burned yesterday, that would equal your TDEE for yesterday. You'll have to wait for midnight to see what FitBit says your TDEE was for today. That seemed a very convoluted and rambling explanation to me.

    Lets try a hands on approach. Here is what FitBit is telling me.
    Friday my estimated FitBit burn was 3,013 which equals my TDEE for that day.
    Saturday my estimated FitBit burn was 2,550 which equals my TDEE for that day.
    Currently my estimated FitBit burn is 1,611 which is not equal to my TDEE for today, just what FitBit has estimated that I have burn so far. I won't know FitBit's estimated TDEE for today until the day is over.
  • PAV8888
    PAV8888 Posts: 14,260 Member
    This may be a stupid question but you all have been so helpful, I thought I'd ask :smile:
    If I turn on my negative adjustments and the value represented is truly a negative number at the end of the day after my adjustment has been made, should I in theory be eating that amount less? For example, if my total cals is 1870 but the negative adjustment represents -105, should I aim to eat 1765 cals that day?

    On a "negative adjustment" day, if you actually want to achieve the deficit you told MFP you want to achieve, the answer is yes.

    Note that MFP will bottom out at 1200 for women/1500 for men, so technically you might still not achieve the dialled in deficit on a super low day. Fitbit has no safeguard and will keep giving you a lower target; however MFP will stop reducing your eating target.

    This doesn't mean that you always have to listen!

    I personally have no desire to extensively eat at less than BMR+100 Cal, which for me is closer to 1700 than 1500.

    So, on the few occasions where a negative adjustment would have me eating less than 1700... I ignore it.

    I go on and have a "red day", accepting that if I am a slug, I will lose weight at a slower rate than I will lose if I am more active.

    Note that I am setup as very active on MFP, so the difference between BMR @ ~1580 and expected TDEE is a substantial 1200 Cal.
  • heybales
    heybales Posts: 18,842 Member
    synacious wrote: »
    d_thomas02 wrote: »
    If I turn on my negative adjustments and the value represented is truly a negative number at the end of the day after my adjustment has been made, should I in theory be eating that amount less? For example, if my total cals is 1870 but the negative adjustment represents -105, should I aim to eat 1765 cals that day?

    Yes.

    MFP calories are an estimated based on what you told MFP what your activity level was. The FitBit correction is based on what FitBit actually measured you doing.

    That's why I bought my FitBit and why I bought a food scale. More accurate estimates of calories in and calories out.

    Agreed. This is why, in my opinion, it is best to keep your MFP activity level at sedentary and the Fitbit food plan at sedentary instead of personalized. Activity level varies, so I feel it's best to just start myself off with the minimum.

    I keep Fitbit at sedentary, but I keep MFP set to lightly active. On days when I do less, Fitbit and MFP match much more closely that way vs. always having a huge number of calories added onto my MFP goal from Fitbit. Negative adjustments will take care of me potentially going down in activity level for the day, but that almost never happens. Actually, I should probably even bump MFP up another level. That way, there's a good, basic goal in place, and Fitbit still works as intended.

    The only kicker with this approach is at end of day.

    Because MFP is calculating your per min (or hr or day) calorie burn based on that setting.

    But once the day is done and you plop down on couch and then later go to bed - you aren't actually even at sedentary level anymore.

    So you meet your MFP adjusted eating goal by say 9 pm - and for 3 more hours MFP will figure you are burning Lightly Active or Active or Sedentary calorie burn.

    The next morning on first sync - your Fitbit will correctly have that time covered as BMR level burn (though it's actually a tad higher until going to bed) - and the prior day's calories will be adjusted.

    So if you exactly met goal at 9 pm - you'll be over the next morning on correction and review of prior day.

    Fortunately if you always go to bed the same - it'll always be the same amount of difference - so you just have to plan to leave that much in the green not meeting your goal.

    But Active level for 3 hrs could be a decent amount of difference.

    So it depends on what helps you plan better - having the realistic value planned on all day long that you can adjust to, and that includes end of day adjustment - or having a low-ball value that you know will be adjusted up as you go along your day.
  • luvmybee
    luvmybee Posts: 58 Member
    I have learned soooo much be reading this thread. Thank you!
  • meredithgir199
    meredithgir199 Posts: 243 Member
    luvmybee wrote: »
    I have learned soooo much be reading this thread. Thank you!

    100% agree! I've learned more on this thread than I have on any other. Thank you all!

  • becalee26
    becalee26 Posts: 185 Member
    Twincle45 wrote: »
    I have a shiny new fitbit charge HR and have been glued to it since xmas day. My question is to those of you that have been using it for a period of time. I have been exercising moderately, cardio and weights, and it gives me back calories throughout the day, so, What do you do with these earned calories? do you ignore them or have you successfully been losing weight by keeping them in you CI<CO totals?

    Sometimes I eat back the calories, sometimes I bank them for a future treat, and sometimes I put them toward my deficit and don't eat any of them back. A lot of it depends on how active I was the day I earned them, and how active I plan to be the next day. I found if I just go for the deficit I run out of energy on day 3.

    I have also found that MFP over estimates the added calories from FitBit, so I usually try not to go over 75% of those calories earned, though lately I have been using FitBit's calories left to determine how much more I will eat as I feel it's more accurate. I still log everything in MFP though. Enjoy your FitBit!

  • becalee26
    becalee26 Posts: 185 Member
    Myfitnesspal way over estimates my "extra calories". Yesterday it gave me 1000 exercise cals for 22000 steps. Maybe I did earn that many, it just seems like too much! I just follow the Fitbit app and how many calories to eat. I lost 20lbs doing that with my charge. . I just stared using HR.
  • heybales
    heybales Posts: 18,842 Member
    becalee26 wrote: »
    Myfitnesspal way over estimates my "extra calories". Yesterday it gave me 1000 exercise cals for 22000 steps. Maybe I did earn that many, it just seems like too much! I just follow the Fitbit app and how many calories to eat. I lost 20lbs doing that with my charge. . I just stared using HR.

    Actually - reread several of the responses above - you did not get the extra1000 calories for 22K steps.
  • PAV8888
    PAV8888 Posts: 14,260 Member
    edited January 2016
    heybales wrote: »
    The only kicker with this approach is at end of day.
    Because MFP is calculating your per min (or hr or day) calorie burn based on that setting.
    But once the day is done and you plop down on couch and then later go to bed - you aren't actually even at sedentary level anymore.
    So you meet your MFP adjusted eating goal by say 9 pm - and for 3 more hours MFP will figure you are burning Lightly Active or Active or Sedentary calorie burn.
    The next morning on first sync - your Fitbit will correctly have that time covered as BMR level burn (though it's actually a tad higher until going to bed) - and the prior day's calories will be adjusted.
    So if you exactly met goal at 9 pm - you'll be over the next morning on correction and review of prior day.
    Fortunately if you always go to bed the same - it'll always be the same amount of difference - so you just have to plan to leave that much in the green not meeting your goal.
    But Active level for 3 hrs could be a decent amount of difference.
    So it depends on what helps you plan better - having the realistic value planned on all day long that you can adjust to, and that includes end of day adjustment - or having a low-ball value that you know will be adjusted up as you go along your day.

    @heybales , based on your FAQ (and what I can estimate from my own data), Fitbit (in a deliberate underestimate) assigns Mifflin St Jeor BMR for time periods during which it does not detect activity.

    Assuming you synchronize Fitbit and MFP when you stop moving for the day, from that point onwards, you will LOSE calories for every minute between that time and midnight [because you will be (according to Fitbit that assigns you BMR calories) less active that what MFP expects you to be (since MFP assigns you BMR x an activity factor calories.]

    The MAXIMUM amount of calories you will lose to midnight can be calculated as follows:

    BMR / 1440 x M x F

    where:
    M = minutes to midnight
    F = 0.2 if you're setup in MFP as Sedentary
    F = 0.4 if you're setup in MFP as Lightly Active
    F = 0.6 if you're setup in MFP as Active
    F = 0.8 if you're setup in MFP as Very Active.
    BMR = http://www.myfitnesspal.com/tools/bmr-calculator
  • Twincle1970
    Twincle1970 Posts: 45 Member
    ^^ I think I got as far as Mifflin then it all went a bit of a tangent :D
  • ASKyle
    ASKyle Posts: 1,475 Member
    dmac_101 wrote: »
    I have a general question about the Charge HR. What kind of battery life should I expect from this device?

    5 days for me.
  • Twincle1970
    Twincle1970 Posts: 45 Member
    ASKyle wrote: »
    dmac_101 wrote: »
    I have a general question about the Charge HR. What kind of battery life should I expect from this device?

    5 days for me.

    2 days for me, even worse it went flat whilst at work so lost 4-5 hours of steps and calories >:)

  • ASKyle
    ASKyle Posts: 1,475 Member
    Twincle45 wrote: »
    ASKyle wrote: »
    dmac_101 wrote: »
    I have a general question about the Charge HR. What kind of battery life should I expect from this device?

    5 days for me.

    2 days for me, even worse it went flat whilst at work so lost 4-5 hours of steps and calories >:)

    Call Fitbit and be firm with them. They're known for having great customer service. Mine wouldn't charge and I was unsure if it was a bad Fitbit or the charger. They ended up sending me an entire new Fitbit and charger with no proof of purchase.
  • d_thomas02
    d_thomas02 Posts: 9,055 Member
    edited January 2016
    Only had mine, well, not even a week yet so take this for what it is worth.

    I stick mine on a charger daily for a quick charge while I'm in the shower, then give it a full 2 hour charge once a week while I'm binge watching Netflix.
  • heybales
    heybales Posts: 18,842 Member
    PAV8888 wrote: »
    heybales wrote: »
    The only kicker with this approach is at end of day.
    Because MFP is calculating your per min (or hr or day) calorie burn based on that setting.
    But once the day is done and you plop down on couch and then later go to bed - you aren't actually even at sedentary level anymore.
    So you meet your MFP adjusted eating goal by say 9 pm - and for 3 more hours MFP will figure you are burning Lightly Active or Active or Sedentary calorie burn.
    The next morning on first sync - your Fitbit will correctly have that time covered as BMR level burn (though it's actually a tad higher until going to bed) - and the prior day's calories will be adjusted.
    So if you exactly met goal at 9 pm - you'll be over the next morning on correction and review of prior day.
    Fortunately if you always go to bed the same - it'll always be the same amount of difference - so you just have to plan to leave that much in the green not meeting your goal.
    But Active level for 3 hrs could be a decent amount of difference.
    So it depends on what helps you plan better - having the realistic value planned on all day long that you can adjust to, and that includes end of day adjustment - or having a low-ball value that you know will be adjusted up as you go along your day.

    @heybales , based on your FAQ (and what I can estimate from my own data), Fitbit (in a deliberate underestimate) assigns Mifflin St Jeor BMR for time periods during which it does not detect activity.

    Assuming you synchronize Fitbit and MFP when you stop moving for the day, from that point onwards, you will LOSE calories for every minute between that time and midnight [because you will be (according to Fitbit that assigns you BMR calories) less active that what MFP expects you to be (since MFP assigns you BMR x an activity factor calories.]

    The MAXIMUM amount of calories you will lose to midnight can be calculated as follows:

    BMR / 1440 x M x F

    where:
    M = minutes to midnight
    F = 0.2 if you're setup in MFP as Sedentary
    F = 0.4 if you're setup in MFP as Lightly Active
    F = 0.6 if you're setup in MFP as Active
    F = 0.8 if you're setup in MFP as Very Active.
    BMR = http://www.myfitnesspal.com/tools/bmr-calculator

    Correct, Correct, Correct, and 0.25 actually for Sedentary.

    For those attempting to follow along - normally the activity levels are 1.25 and ect, but since you want to subtract what Fitbit will report (BMR) from what MFP is estimating (BMR x F) - merely multiply but leaving out the 1.x to exclude the BMR.

    So great formula for perhaps doing for the weekday nights where you become inactive at certain time - and weekend nights where perhaps it's different. Only have to update every 10 lbs lost when numbers change enough to matter.
    So that's not bad at all.

    Then just have those 2 figures in mind, perhaps rounded to something easy to remember - and always leave that much in the green.
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