Garmin watch calories burned.

5512bf
5512bf Posts: 389 Member
I have a forerunner 225 with optical hr. I just had a lactic threshold test done and tweaked my train zones based on that. Ever since my calorie burned tally have been a lot less. I'm 180 lbs and some of the numbers garmin is giving me is in the 75-85 calories per mile range, then the next mile could be 110. The hr data looks steady without losing connection which happens from time to time with the watch. My 18 mile long run this morning recorded 1650 calories, which seems way low to me. Anyone else get number that seems off.
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Replies

  • litsy3
    litsy3 Posts: 783 Member
    Mine told me I burned 1200 calories running 20 miles this morning! I think it's because I have a very high max but rarely get anywhere near it, so it assumes I am not working very hard. It also massively underestimates for interval training, because your heart rate goes back down in the recovery intervals, and takes a while to get back up on the reps, so it just notices that you're not spending very long in the harder zones (I imagine that would be the case for any HRM though). I usually just ignore it for calorie counting and use an estimate based on the .63x body weight in lbs x distance formula.
  • MNLittleFinn
    MNLittleFinn Posts: 4,271 Member
    Garmin is the lowest for the numbers, as compared to Strava and others on the same data. That being said, I use the Garmin numbers for my calories burned so I can know I'm not overestimating burn.
  • runbabarun
    runbabarun Posts: 89 Member
    Very likely the case. Not the same thing, but the same 3.5 route at same easy effort without an HRM was 500 calories, since I started using the rhythm+ with FR 230 and setting the zones, the same run is about 400 cals for me.
  • jacksonpt
    jacksonpt Posts: 10,413 Member
    That sounds right to me... based on what I think I know about calorie estimates and from my experience with my garmins.
  • 99clmsntgr
    99clmsntgr Posts: 777 Member
    I ignore what the Garmin says. I'll take the average-for-the-workout heart rate data over to here: shapesense.com/fitness-exercise/calculators/heart-rate-based-calorie-burn-calculator.shtml and calculate it out.

    That same site has an activity based calculator, which includes running, walking, etc., based on paces. It's a little lower calculated calories than the MFP calculator.
  • litsy3
    litsy3 Posts: 783 Member
    I use the Garmin numbers for my calories burned so I can know I'm not overestimating burn.

    I was doing that at first, but some of the burns were so pitifully low that they were just silly! (250 cals for a track session including warm-up and cool-down totalling 8 miles, anyone?).
  • runbabarun
    runbabarun Posts: 89 Member
    litsy3 wrote: »

    I was doing that at first, but some of the burns were so pitifully low that they were just silly! (250 cals for a track session including warm-up and cool-down totalling 8 miles, anyone?).

    That sounds like a bad joke!

  • 5512bf
    5512bf Posts: 389 Member
    litsy3 wrote: »
    I use the Garmin numbers for my calories burned so I can know I'm not overestimating burn.

    I was doing that at first, but some of the burns were so pitifully low that they were just silly! (250 cals for a track session including warm-up and cool-down totalling 8 miles, anyone?).

    The insult to the Garmin calculations is since I use the calorie adjustment activity tracker with it, a lot of times it'll adjust me down even further later in the day. I'm always like WTF, I just ran 10 miles and you're allowing me 750 calories? If i was 100 lbs maybe, but at 180 lbs it should be closer to 125 calories a mile. I just makes it difficult to accurately track calories in/out. I'm not trying to lose a ton of weight but with 65-70 miles a week I need to balance properly fueling for (3-4) 10-20 miles runs each week and recovery without adding weight, which is easy to do when you are eating 3000+ calories a day.
  • jacksonpt
    jacksonpt Posts: 10,413 Member
    5512bf wrote: »
    litsy3 wrote: »
    I use the Garmin numbers for my calories burned so I can know I'm not overestimating burn.

    I was doing that at first, but some of the burns were so pitifully low that they were just silly! (250 cals for a track session including warm-up and cool-down totalling 8 miles, anyone?).

    The insult to the Garmin calculations is since I use the calorie adjustment activity tracker with it, a lot of times it'll adjust me down even further later in the day. I'm always like WTF, I just ran 10 miles and you're allowing me 750 calories? If i was 100 lbs maybe, but at 180 lbs it should be closer to 125 calories a mile. I just makes it difficult to accurately track calories in/out. I'm not trying to lose a ton of weight but with 65-70 miles a week I need to balance properly fueling for (3-4) 10-20 miles runs each week and recovery without adding weight, which is easy to do when you are eating 3000+ calories a day.

    Just out of curiosity... if you know that @ 180lbs you should be burning about 125 cals per mile, why are you even paying attention to Garmin's estimates? Just turn the calorie counting off if you already know what you're burning.
  • 5512bf
    5512bf Posts: 389 Member
    jacksonpt wrote: »
    5512bf wrote: »
    litsy3 wrote: »
    I use the Garmin numbers for my calories burned so I can know I'm not overestimating burn.

    I was doing that at first, but some of the burns were so pitifully low that they were just silly! (250 cals for a track session including warm-up and cool-down totalling 8 miles, anyone?).

    The insult to the Garmin calculations is since I use the calorie adjustment activity tracker with it, a lot of times it'll adjust me down even further later in the day. I'm always like WTF, I just ran 10 miles and you're allowing me 750 calories? If i was 100 lbs maybe, but at 180 lbs it should be closer to 125 calories a mile. I just makes it difficult to accurately track calories in/out. I'm not trying to lose a ton of weight but with 65-70 miles a week I need to balance properly fueling for (3-4) 10-20 miles runs each week and recovery without adding weight, which is easy to do when you are eating 3000+ calories a day.

    Just out of curiosity... if you know that @ 180lbs you should be burning about 125 cals per mile, why are you even paying attention to Garmin's estimates? Just turn the calorie counting off if you already know what you're burning.

    Mainly just because of the ease of letting the app do the work. This just really started a few weeks ago when I manually adjusted my training zones to reflect a hr test. Before it was generally close, now that my max hr is set to 200, z4 threshold is 172 and my z3 aerobic doesn't kick in until 145, the bulk of my runs are in upper z2 warmup, which I think is why @litsy3 & I are getting the unrealistic calorie counts. The difference garmin calculates the same pace run at an average HR of 140 & 145 is 75 calories to 115. Over the course of 18-20 mile long run that can be a big difference, like a 6 pack of beer difference :)
  • litsy3
    litsy3 Posts: 783 Member
    That's why I just log the .63 x 125lbs x miles - it comes out slightly lower than the MFP estimates, but not crazy low and all I want is a general sense of how many calories I'm burning. But I'm not hugely bothered about accuracy in any case - if I'm eating too much I'll know in the medium-term as I'll put on weight, and if I'm underfuelled I know because of how I feel.
  • Robbnva
    Robbnva Posts: 590 Member
    litsy3 wrote: »
    That's why I just log the .63 x 125lbs x miles - it comes out slightly lower than the MFP estimates, but not crazy low and all I want is a general sense of how many calories I'm burning. But I'm not hugely bothered about accuracy in any case - if I'm eating too much I'll know in the medium-term as I'll put on weight, and if I'm underfuelled I know because of how I feel.

    Where is that formula from?
  • litsy3
    litsy3 Posts: 783 Member
    http://www.runnersworld.com/weight-loss/how-many-calories-are-you-really-burning

    I've seen it in various places; I mainly just use it as it's the most conservative estimate (except my garmin's HRM!) so I can be reasonably confident I'm not over-estimating.
  • The_Enginerd
    The_Enginerd Posts: 3,973 Member
    I use the 0.63 x weight x miles = Net Calories Burned formula as well and it's accurate for me per ~2 years of experience at mileage ranging from 20-25 MPW to 55 MPW. My Garmin is reasonably close to this over the long run (looking at a week's worth of calories burned), but it varies from run to run fairly significantly due to the weather's effect on HR.
  • Robbnva
    Robbnva Posts: 590 Member
    edited August 2016
    But what is the .63 based off of? What number would you use to calculate walks? What about faster runs vs slower runs?
  • pondee629
    pondee629 Posts: 2,487 Member
    Robbnva wrote: »
    But what is the .63 based off of? What number would you use to calculate walks? What about faster runs vs slower runs?

    I think walks is .33. Speed does not matter in this calculation. Walking is when at least one foot is always on the ground. Running is when during the stride both feet are off the ground.

    Me, I just count the steps off my I-Phone. I may be under counting calories spent, but you aren't supposed to eat all of them back anyway because they are often over estimated.
  • 5512bf
    5512bf Posts: 389 Member
    edited August 2016
    I've basically had to turn off my Garmin calorie calculations from importing into MFP. Yesterdays 15 mile run gave me 1245 calories. The odd thing is the same pace/hr/time/stride rate early in the run will give my 15-20 calories a mile more than if it was done later in the run. I can't seem to figure out the math on Garmins part.

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  • Robbnva
    Robbnva Posts: 590 Member
    Hmm I think I'll start using that for my calculations. Thanks
  • The_Enginerd
    The_Enginerd Posts: 3,973 Member
    edited August 2016
    Robbnva wrote: »
    But what is the .63 based off of? What number would you use to calculate walks? What about faster runs vs slower runs?

    The multiplier is 0.30 for walking. The calories/mile is pretty constant at different running speeds.

    edit: The multiplier is based off of studies. It varies from individual to individual depending on their running economy, but it's more accurate that any of the other calculators I've seen. Most tend to over estimate calories burned.
  • STrooper
    STrooper Posts: 659 Member
    I have a TomTom with the optical (Mio) sensor so this may not be relevant.

    In the current version, they do not use HR as the basis for calorie calculation. Instead, the HR data is used for training zone but it is MET table data that the watch uses for estimating the calorie expenditure. (They say) this is to prevent someone from using the GPS only function of the watch without turning on the optical sensor and getting "zeroes" from the HR calculation. Now why someone would by an optical sensor HRM and not use it is beyond me (though you can forget to set it is you reset the watch back to factory conditions). Makes me wonder if Garmin is doing something similar for a similar reason (do you get zero calorie expenditure with the optical sensor turned off?).

    OTOH, my Mio Global Link optical HR sensor (on the other arm, giving nearly identical HR data) goes to one of my favorite programs (iCardio Digifit or now FitDigits) where I know that the HR data is being used to calculate calorie expenditure because they publish the formula that is used for the calculation. Granted, that formula requires a lot more basic setup and tends to give higher calorie expenditure (total, not net). But it also uses the data to estimate the percentage of calories burned from fat versus carbs based upon a realistic input of your heart rate zones (with several methods available to set them).