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Garmin 235 Calorie burn??? There is no way this is accurate

Hi,

New to the forums as well as a Garmin 235. There's quite a few things I am not 100% satisfied with, however the Calorie burn is absurd. I attached an imagine of how many calories I supposedly burned yesterday. Has anyone else had unbelievably inaccurate information like this?

0 timgrose over 8 years ago

There are quite a few other threads on the subject.

Unclear from that would you actually did however?

0 AndreasPettas over 8 years ago

As for activities. I did 30 minutes on an elliptical at the gym plus a regular 8-5 office job.

0 hllb over 8 years ago

I haven't had an issue with mine. Definitely not anything like yours is showing. My daily calorie burn ends up a couple hundred calories higher than my fitbit. I think reality is somewhere in between the two.

0 gpb11 over 8 years ago

Has anyone else had unbelievably inaccurate information like this?

Yes, I have seen ridiculous calorie estimates every time I've had grossly wrong user stats entered into a device. Also I've had those when a device was brand new and hadn't "learned" me.

Make sure you have everything set up properly including your min and max HR if you're using HR monitoring. Your super high activity calories suggests your maxHR is set way too low.

BTW, if finding your max HR involved a calculator instead of copious sweat and discomfort, it's probably as grossly inaccurate as calculating your shoe size from your height.

0 MrGiggler over 8 years ago

I have the opposite problem. I always get a low calorie burn. My last long run was 683 calories per Garmin and 914 calories per Strava. I did a 3 mile short run yesterday (1.5 miles easy and 1.5 miles tempo) that was 245 calories per Garmin and 362 calories per Strava. A 120 calorie discrepancy on such a short distance is unacceptable in my opinion. I kinda depend on the numbers being somewhat accurate because I need to make sure I'm eating enough calories for maintenance and recovery. Also, the recovery advisor will sometimes underestimate my required recovery.

I started using Fitbit back in April of last year and switched to Garmin in early December. Fitbit and Strava were always really close on the calorie estimate so I'm inclined to believe Strava as it seems like Garmin is the odd man out.

0 gpb11 over 8 years ago

I have the opposite problem.

Unless you're pretty slight of build, that Garmin figure sounds a little low. As above, look to all your parameters and ensure they're set properly.

One note though, the discrepancy between Garmin and Strava is nothing new, it's been around in some form for far longer than the 235. I saw wide discrepancies with my Garmin 610, Fenix3, and 920xt. http://forums.roadbikereview.com/general-cycling-discussion/why-garmin-strava-calculates-differently-301196.html

In April for kicks I did a 10 mile run with the Strava iPhone app, 610, F3, and 920xt at the same time. The 610 reported 947kcal, the F3 935kcal, the 920xt 933kcal, and Strava reported 1520kcal. On other runs where the Garmin data goes right into Strava I'd see stuff like 562C vs 811C for the exact same data. I always figured the correct number was somewhere in between the two.

It looks like Strava doesn't use HR data for calorie burn: https://strava.zendesk.com/entries/20959327-Calorie-Calculation
.... and interestingly in a run I did today with the 235 and my 920xt without an HR strap, the 235 reports 469kcal vs the 920xt's 621kcal. When I've worn both and used my HRM-RUN the calorie reports were very close, within a couple % points.

Also worth a read:
http://www.dcrainmaker.com/2010/11/how-calorie-measurement-works-on-garmin.html

0 timgrose over 8 years ago

I also think Strava includes BMR calories whereas Garmin does not. As such Strava will be higher on that alone.

0 MrGiggler over 8 years ago

Unless you're pretty slight of build, that Garmin figure sounds a little low. As above, look to all your parameters and ensure they're set properly.

One note though, the discrepancy between Garmin and Strava is nothing new, it's been around in some form for far longer than the 235. I saw wide discrepancies with my Garmin 610, Fenix3, and 920xt. http://forums.roadbikereview.com/general-cycling-discussion/why-garmin-strava-calculates-differently-301196.html

In April for kicks I did a 10 mile run with the Strava iPhone app, 610, F3, and 920xt at the same time. The 610 reported 947kcal, the F3 935kcal, the 920xt 933kcal, and Strava reported 1520kcal. On other runs where the Garmin data goes right into Strava I'd see stuff like 562C vs 811C for the exact same data. I always figured the correct number was somewhere in between the two.

It looks like Strava doesn't use HR data for calorie burn: https://strava.zendesk.com/entries/20959327-Calorie-Calculation
.... and interestingly in a run I did today with the 235 and my 920xt without an HR strap, the 235 reports 469kcal vs the 920xt's 621kcal. When I've worn both and used my HRM-RUN the calorie reports were very close, within a couple % points.

Also worth a read:
http://www.dcrainmaker.com/2010/11/how-calorie-measurement-works-on-garmin.html

Thanks for the detailed response, that gives me a lot of info to troubleshoot on. At 70" tall and 150lbs I would consider myself to be average build for a runner. I think all my data is accurate (height, weight and age). I usually weight myself every other day with a Fitbit Aria and then I use MyFitnessPal which then sends that data to my Garmin and Strava accounts so it's all as accurate as can be. I suppose I will choose a calorie burn somewhere in between the two. Is it possible that Garmin's V02 Max estimate plays into their calorie burn equation? I have noticed that my V02 max number seems to go up the more I use the 235, especially when doing threshold running.

0 gpb11 over 8 years ago

Glad the info helps. We're of similar height, though you're a bit leaner than I am currently for whatever that's worth.

Yes, it appears Garmin uses heartrate and VO2max (or the underlying HRV data) as part of the calorie count. See http://www.firstbeat.com/consumer-products/garmin/ and scroll down to the Forerunner 235/230 section. I believe the maxHR setting also has an effect on these figures.

The watch's estimate of your VO2max (and I emphasize that it's an estimate) will hone with additional outdoor GPS running; this is much of what people mean when they suggest letting the watch "learn you" over several runs before giving much credence to things like calorie counts or VO2max.

0 Former Member over 4 years ago

A recent study showed that Fit bit was the most accurate of the devices for estimating calories but that even it had an average error of 25%.