Calorie calculations

It may well be wrong, but how do you know the other is right? Do you use a HR strap? If the other Calorie burn is from just a calculation, then it's might be based on the average person and not the average person in good athletic shape. An HR strap helps some to determine that and will give different burns for the same activity based on how your heart behaves.

In the end, it's all just an educated guess that we can argue about. We wouldn't be able to wear and afford the sensors needed to get a scientifically accurate number, and even that would likely be argued about by the Phd's.

For me it comes down to which number benefits me the most. If I'm trying to loose weight, I'd use the lower of the two. If trying to gain mass or bragging rights I'd use the higher.

But as I prefaced this post, your 910xt may well be wrong. You'd do better I'd think to get in the 910xt forum and see what other 910xt users have had similar issues.

My Garmin 310XT.

I also found wornf calorie calculation during past 2 weeks but just notice today. the calorie was low about 30-50% if comparinf from previous ride which same duration and tempo.
Is there any bug for calorie calculation? Please advise how should I solve it.

Thanks,
Vasin
Thailand

You can edit most any of the fields once you've uploaded to Garmin Connect or whatever fitness site or software you use. As far as changing it on your device, you can't unless you want to make your own hack.

Your Calorie count is not going to be exactly right ever. 30% may well be as good as you get for any one activity. But take months worth of activities and average them together and it will probably be very close. IMO, it's not unreasonable to see different Calorie burn for the same activities.

Still your device may be wrong, but you've given no clues about it, nor defended very well why you think it's wrong. Tell use whether you use a HR strap. Where are you getting the data that says your Calorie burn is wrong?

Also know that when you come to this forum, you are talking to other users. You will seldom ever get a response from Garmin here unless you are in the Garmin Express sub-forum, and that's only because they've had a steep user learning curve for a new product release, IMO.

I have noticed the same thing. I am a runner and always use a heart rate monitor during exercise. Prior to getting my Garmin Forerunner 15, I would use the heartrate-based calorie calculator at shapesense.com to determine the number of calories I burned based on my average heart rate. This morning after my workout Garmin calculated I had burned 220 calories (average heart rate was 138 for 30 minutes of exercise). When I plugged the data into the Shapsense calculator, it indicated 293 calories. That's over 30% more. All the data used is the same for both (age, weight, gender, average HR, duration), so I would not expect such a difference. I know the Shapesense calculation is based on industry accepted standards. Intend to inquire with Garmin, although many posts seem to indicate I shouldn't expect any knid of response from Garmin.

Everyone always wants the higher number to be right.

The web site may give you a number you like, but how do you know it's right? Have you seen the data the web site you prefer base their numbers on? Do you know who they tested and how? My guess (as a scientist, but I'm not a physiologist) just based on the various numbers I get from various sites/software from the exact same track is that the correlation between heart rate and calorie burn is there but not that well defined, and the errors can be large. Something like the 220 - age maximum heart rate formula, which, if you look at the actual data, doesn't fit very well at all. (My own maximum heart rate as measured several times last year is 175, but I'm 60 years old.) Calorie numbers based on heart rate given by devices or web sites are estimates, not measurements. So far as I know, outside of a lab only cyclists with power meters are measuring anything even closely related to calorie burn.

Agreed - I'm not surprised by the 30% difference - without a detailed knowledge of your body composition and extensive monitoring in a lab anything is going to be a very rough estimate. What are you interested in the calorific value for?

I've just recently started having a problem with the calorie estimations.

I am a 5'5'', 120lbs. female.

Prior to December, I was consistently averaging about 525 calories burned for a 6 mile run (10km), for about 11 months.

Then one day in late November I got a reading for 320 for a 6 mile run. I thought this was strange, but wrote it off as an anomaly. However, even since then, I have been consistently averaging 320 calories burned for a 6 mile run.

I changed nothing in the settings. The only thing I can think of is I changed the battery in the HRM around that time. I do wear a heart rate monitor strap each time.

What the heck?? There is no way that almost an hour of running (lots of hills usually) burns only 300 calories now!!

I've just looked through my calorie counts for runs and they remain pretty consistent over a long period of time and roughly correlate with TE (for a given distance). For a 10K race effort and a TE of 5 I burn about 670 to 700 Calories at my pace (about 7 min miles) I am 6ft 3 and about 175 lbs. So on that basis your original figures look OK and the current look too low. It may be worth doing a full reset and seeing if the watch reverts - which model is it?

Noticed a 50% reduction in calorie count since updating to new Garmin 510 software. Same exact route, same bike, same elapsed time, etc. Something happened on the Garmin side in the calculations.

I also found this thread because of a similar issue. Around Christmas activities that should be comparable for duration and avr. HR are consistently lower. While I'd certainly prefer to believe higher numbers, it's the consistency that I care about. If Garmin came out to explain that they have a new algorithm, and why this 'new normal' is better/more accurate I'd be entirely satisfied. But as of now I'm more than curious why a 10k with a 155 avr. HR is 500 calories when one with a 142 used to be 700.