Calorie Count and Distance

[Livingm2]

Hi,

I've been using my ChargeHR for just over a month now and have a query regarding potential low calorie burn and distance ...

When exercising, I've noticed that my calorie burn rate is lower than what I would expect it to be. My heartrate looks pretty accurate on the basis of it spiking and dipping doing various forms of interval training. On the other hand, my husband's count seems pretty high! I appreciate there will be differences when you take into body weight account etc etc ...

I've also noticed that when tracking distance, my ChargeHR can be anywhere between 0.5 and 1km less than I've actually travelled - I've compared this with both walking/running outdoors and on a treadmill.

I used the Help guide to reset the device, but still encountering the same issues

Anyone else in the same boat??

[lizfortney]

I do the exact same walk twice a day.  I have measured on my car odometer and it is exactly 3 miles.  It takes me 39 minutes (plus or minus 30 seconds) every time.  My heartrate according to my Charge HR varies as much as 50 beats per minute between walks, the distance reported varies by up to .75 miles, and the steps counted vary by up to 1,000 steps.  The calorie burn varies by up to 50 calories, and usually shows lower when my heartrate reports higher.  I am now questioning the validity of all of the numbers reported by my FitBit.  Thinking of changing to Garmin.

[Livingm2]

Thanks for taking the time to reply ...

My husband and I done the exact same walk together and there was an anomoly with the distance! So infuriating!!

Wish I'd read the Help Forum before I bought my FitBit ... I'll keep going with it for now but there's always a niggle about the validity of the numbers!

Good luck with the Garmin!! 🙂

[SebringDon]

@Livingm2 @lizfortney

I notice that neither of you mention taking your phone along and using MobileRun to track the actual GPS distance. That means that FitBit is calculating your distance based on your step count multiplied by your average stride length, either the default based on your height and sex, or the one you manually entered. 

In reality, your stride length varies by quite a bit, depending on how fast you're stepping and how much you're stretching out. I use MobileRun and keep a spreadsheet that calculates my stride for each walk that I log. I've found my average stride over 109 logged walks is 30.3 inches, but it has varied from 26.8 to 40.9 inches on individual walks, depending on how I was moving. There's a fair correlation between pace and stride length, but even that's not precise. Generally, the faster my pace, the longer my stride and the more steps per minute.

Also remember that your calorie burn during exercise includes your BMR calories, so you'll find that you actually burn more calories for a given distance if you take longer to cover that distance. I average 179.3 calories per mile and 8.9 calories per minute, but those two figures appear in an inverse relationship, with my highest calorie burns per minute on those walks with the lowest calorie burns per mile... because it takes me less time to cover a mile, so the overall calorie burn is lower.

This chart, showing cals burned per mile against speed, illustrates that inverse relationship pretty clearly. The red line is speed, the blue line is calorie burn per mile. The lower the speed, the higher the calorie burn per mile. The spikes with the biggest differences are walks with my dog, when I'm really poking along letting him sniff everything.

Hope this helps!

[lizfortney]

Thanks for the information. I am assuming that the program you mentioned
then links to Fit Bit somehow? Prior to using FitBit, I was using
RunKeeper. Do you know it this will link to FitBit and it so, how do I do
that?



Thanks very much.

[SebringDon]

@lizfortney

MobileRun is the name for the "Track Your Exercise" portion of the Fitbit mobile app. Scroll down to "Track Your Exercise" and tap. Click the stopwatch icon in the upper-right corner, wait for the GPS circle to show GPS is active, then push the start button. Optionally, before pressing start, choose in the lower section whether you want to track a walk, run or hike, if you want to use voice cues, and how often those voice cues should occur.

You'll get a screen with a timer, pace and distance indicators, and a "pause" button. Press the "pause" button when you're finished with your walk and you'll also see a stop button displayed. Press AND HOLD the stop button until the exercise indicates it has ended.

Hope this helps!

[lizfortney]

THANK YOU VERY MUCH!! I had no idea that the GPS feature would take care of
the distance and pace issue! I have been using this for the past few days
and it is now very consistent. I really appreciate your help.

[Sueb5]

I've had the same did 4 laps of the track today which should be 6.3km, but it only registered 4.5km. Maybe the fit bin is just fit for the bin

[SebringDon]

@Sueb5

Have you tried the trip around the track with MobileRun?

[Evo2]

Exactly my problem. 3.5 mile jog distance, Google maps, car say. 34 mins 10 minute a mile.

Yet my fitbit says 2.7miles. 

And I'm not burning 3000 to 4000 calories a day, utter rubbish. I could eat 3 12 pizzas a day and lose weight if that was true. My height and weight calculator says I burn 2,300 calories a day, hence I need to eat 1,800 calories a day to lose weight at end of week. 

[RingoRingo]

Wow!!! Awesome reply. ❤️ Your explanation was extremely helpful. Thank you!!!