Does Blaze Calculate Calories Burned Using HR

[SunsetRunner]

Hello,

I am wondering if the Blaze watch calculates calories burned throughout the day using your heart rate. I have seen mixed reviews on this topic. Will Blaze automatically use HR along with your body stats to calculate calories burned? Or must you manually log a workout on the watch to make it factor in HR when calculating calories burned. 

I am extremely surprised that this is such an issue with the fitbit models. One would think that if the device is capable of calculating HR this would be factored into the algorithm that determines calories burned without requiring the user to take additional steps.

[SteveH · Accepted solution]

Fitbit calculates calories burned based on a combination of your step activity and your heart rate (for those models that have this function). It also takes into account your BMR calories (those you burn just keeping your body alive) which are calculated from your profile settings.

You don't need to manually log an activity for this to work. Indeed, if you do manually log an activity then the calories that were tracked (taking into account your heart rate) will be overwritten by the manual entry. So, the most accurate calorie burn calculations are when the activity is mainly step based and you let the fitbit track it.

[AngelaMa]

Hello @SunsetRunner welcome to the Fitbit Community! It's great to have you here 🙂 @SteveH thanks for your amazing cooperation! 😉 @SunsetRunner you can read more about how Fitbit estimates the calorie burn on this post. 

I'll be around if you have any questions! 😉 

[CanyonGirl]

My access is denied to the link you suggest.  How do I find out how the Blaze calculates calories burned.  Is it some combination of my weight, HR, etc.? If it is based on steps taken, how can it calculate my strenght (weight) and stationary bike training? 

[Rich_Laue]

@CanyonGirl looks as if the post or thread was deleted or moved.

Doesn't matter, s roll to the bottom of this page, tap or click on help. This will take you to the interactive help guide. Type calories into the search bar.  There will be several hits, one of which is the calorie FAQ.

[AngelaMa]

Welcome to the Fitbit Community @CanyonGirl! It's great to have you here 😉 I just updated the link thanks for letting me know it was not working. @Rich_Laue thanks for your cooperation!

I'll be around if you have any questions! 

[Puravida5169]

So just confirming from after reading the suggested link. The blaze DOES NOT work out your daily burn based on your heart rate throughout the day. It only works it out from logging activities and your bmr.

For example: If i have done exercise and my pulse is raised after the session (and activity has been ended) it will not calculate extra calorie burn. 

Is this correct?

[SteveH]

@Puravida5169 I don't think that is correct. The calorie burn figures are derived partly from your BMR calories (as described in that article) and your activity calories. Your activity calories are calculated using both your detected movement and your heart rate. Starting and stopping an activity doesn't affect the measured calories.

[Puravida5169]

Thanks for replying.
So if I went to the gym and did an hours worth of exercise without logging anything. Just wearing the watch as usual, the Fitbit will detect my raised HR and adjust the burnt calories to suit?
When buying the blaze I assumed that having the HR feature it would do this but I didn't think the answer given in the link above really makes that obvious. The BMR for the day can be calculated simply by entering your age height weight etc. if my body burns 1600 cals a day it is divided by 24 hrs and then allocated each hour as what I have burnt for the day.
Does that make sense? It kind of sounds like they get your daily burn based on your entered info and just add on any exercise you've entered. Without actually using your HR info

Sent from my iPad

[SteveH]

That's more or less correct.

The BMR calories are calculated automatically at a constant rate 24 hour per day and it's these that are covered by the help article. You get additional calories on top of that from activity. If the activity was tracked by your fitbit then your HR is taken into account along with your steps. If you manually log an activity (rather than let your track it or if you forget to wear your fitbit) then your HR is not taken into account.

[AngelaMa]

Hello @Puravida5169! As @SteveH mentioned if the activity was tracked by your fitbit then your HR is taken into account along with your steps. If you manually log an activity and you where not wearing your tracker then your HR is not taken into account. 

Catch you later! 😉 

[Puravida5169]

Hello, thanks for your reply (i just saw it). If i go to the gym and wear my blaze and do not press any buttons to start an activity, just workout - the fitbit will dectect my increased pulse and adjust my calorie intake for the day appropriately. I am also assuming that if i do a workout and do use the watch to track (start at beginning of workout and stop at the end), it is pretty much doing the same thing but is programmed to logg it as an exercise which will show up on my fitbit dash board. Correct?

Also one other question. If i do exercises such as a body pump class or weights where i am not taking steps but moving my arms alot, am i better of logging it AFTER the workout? It seems that by doing this the "steps" (arm movements) are not added to your daily step total.

Just a bit confused! Thanks

[SteveH]

Re the first point: correct, you get the same results whether or not you push any buttons.

There is a difference between tracking an exercise in this way (which just highlights a period of activity) and manually logging an activity. When you manually log an activity it will overwrite the calories tracked with those for the manual entry. If the manually logged activity is a step based activity, like walking, then it will also overwrite the steps.

[Rich_Laue]

Another point about using the exercise function is that it will displayyour steps and calories for that per of in finer detail

[Puravida5169]

Thankyou Steve and rich. So If i manually log an activity it will ask me to enter the calories burnt - and i could easily over or under estimate the calories burnt. So i am better off pushing the button and tracking it as i do it. It will be more accurate. 

And for a gym class like boxing or body pump (weights) where i am using my arms the step count will be high. Would i be better off wearing it and track the time and calories. Then once the session is finished, take note of the time started and finished and the calories. Then enter it as a manual activity (and clear the previous tracked exercise. That way the 'steps' (arm movements) would not be included. 

[SteveH]

I don't think there are any hard and fast rules.

What you could do is let your Blaze track the activity itself and note the times and the steps/calories recorded. Then manually log the activity (depending on what activity you log it may be able to estimate calories itself). Compare the two sets of results. If they are not far off then you can forget about manually logging it next time. If they are very different then I would go for the manually logged activity if it calculated the calories.

Note you can always delete the manually logged activity and your stats will go back to as they were before you logged it so you're safe to experiment.

[Puravida5169]

Thankyou steve. 

[AngelaMa]

Hello @SteveH, @Puravida5169 and @Rich_Laue! @Puravida5169 I think the idea shared by @SteveH to test the activity it's great, keep me posted about the results! @Rich_Laue thanks for your cooperation! 

Catch you later! 

[IamDrKarla]

Hello Fitbit Community.  I am in desperate need of understanding.  I just bought the NEW fitbit Blaze.  While I understand that there are no perfect instruments, I am REALLY struggling with this one.  I have read every blog I can find and I have followed all suggestions, from resetting the fit bit to resyncing, to wiping my arm down, to removing the watch and replacing it.  Nothing has worked.  

In cardio, it rarely if ever tracks 1.  the correct amount of time in cardio,  2.  the correct heart rate - IF it tracks it at all, so how is it possible to track the correct calories burned.  In addition to that, almost everything I am scanning it to the food scanner is located but is usually 20-50 calories higher than what is posited on the nutritional labels.  I am very confused at how any of this is 1.  effective and 2.  useful.  I have read almost every blog.  I have rest the watch.  I have wiped down my wrist and nothing helps.  I even took the chest strap device AND another wrist strap device to assist me in determining if my fitbit was accurate, or even remotely close.  Both chest and wrist straps are within 5 BPM and within about 2-3 calories of each other.  Example - I worked out today for 63 minutes at a gym that tracks HR and BPM on the board.  

Chest and wrist strap average HR (Ave 150) and Calories burned (586) matched what the gym had.  Total time in class matched within 2-3 minutes.  Fit bit tracked me in cardio for 17 minutes with a HR of 120, IF it measured at all.  It also said I burned about 76 calories.  

I love that the app is keeping me on track but I also know that part of my past struggles have been not eating enough.  So failure of the fitbit to recognize these additional calories burned has the potential to put me into a place where I am burning my lean muscle and not the fat.  Can anyone help me with this or do I need to just accept what most of the blogs are saying - that the watch really does nothing more than count my steps?

[Gareth575]

Your Fitbit will calculate calories burned primarily on your heart rate. I will work out using the exercise tab on the watch and then complete an exercise with out entering it on the watch. It makes not difference to calories burned! Entering it manually is there if you forget to wear your watch or you take it off for swimming and so on. All the other functions like steps are there for your reference. Again these stats make no difference to calories burned. Remember Fitbit adds BMR and active calories together (e.g. One hour of running = 80 cals BMR plus 800 active calories totalling 880 cals burned) I have had numerous trackers and I am confident Fitbit over compensate on cals burned. Not so much on strenuous exercise but more on low impact such as walking and everyday activities. I get around this by automatically entering 500 cals to my food intake before eating anything st all.