Who to believe ??

[zootnanook]

Probably my own fault but I use a Garmin Edge 800 which I upload to the Garmin Connect site and also to the Strava site, I also use Cyclemeter on the iphone, but there's a huge difference in calorie count from all 3, today I rode 30 miles and Garmin claim I burned 598 calories, Strava 1112 calories and Cyclemeter1819 calories, all 3 have the same details entered about weight, height and bike etc etc, who do I believe ??

 

[Typhon]

I don't think Strava factors in your weight in the calculation and it just asks you for it so that it can rank you in different weight categories (which you can see if you have premium). I have lost about 2 stone over the last 6 months and I have entered that on Strava but it tells me I burn almost exactly the same amount every time I do my training loop.

It's odd that your garmin tells you you burn so little, 600 cals in 30 miles seems unrealistically low and my garmin 500 always tells me I've burned a lot more than Strava.

Strava's calculation seems to be based on a super fit 10 stone type cyclist. I have looked up calories burned on various different sites and they all say that for my height and weight - 6'2" and 13 stone, I burn about 800-900 calories per hour on a vigorous ride. That is pretty much what my garmin tells me but Strava always tells me I burn about 50-60% of that.

Perhaps it's wishful thinking but I believe the garmin and those sites I researched. How much you burned will depend upon your height, weight etc but if you're not a stick insect and that ride took you two hours or so I'd say that the 1800 figure from cyclemeter is probably the most accurate.

 

[Sittingduck]

Imho Strava isn't that far off, in comparison to some of the other things.

 

[vickster]

30-40 calories a mile seems a decent estimate (unless you are very heavy and riding up hills then probably more), so Strava sounds most likely

 

[Kies]

Also suprised what your Garmin is telling you. Check your weight and height inputs.
I take the Garmin figure and reduce it by a third as a fairly accurate calculation.

 

[Mr Haematocrit]

Would not believe either, after having VO2 tests done, I know they are both noticeably out for me.

The most accurate method of measuring calorie burn is through VO2 testing ... To turn the fuel you receive from food into energy, you require oxygen. Because there is a direct relationship between how much oxygen you use and how much energy you burn, by measuring the oxygen to carbon dioxide exchange through VO2 testing, you will get a fairly precise gauge of how many calories you're burning..... Everyone's calorie burn is different as VO2 efficiency is not a fixed value.... if you want to know your calorie burn undertake a VO2 test, anything else is a best guess​

 

[Ningishzidda]

Which of the devices was closest to your pre-ride calculation?

 

[Mr Haematocrit]

Which of the devices was closest to your pre-ride calculation?

None were even close when doing high intensity tasks. When I was recently tested for my VO2 max the actual numbers were noticeable enough for me to dismiss the values presented by these websites, even as an average. At the time I think garmin was about 12% out for me... But that's the point, the inaccuracy value may be different for you.
I have at my last test a VO2 Max of 69 ml/kg/min and this is what calculated my calorific burn rate. Unless your VO2 Max is the same as mine, the percentage of error on these websites remains unknown.

Your best guess is as good as any websites guess, you can't believe any..... If you want to know, go for a VO2 Max test.

 

[HLaB]

If I were looking to lose weight, I'd go with the lower (Garmin Connect) value for now and double check the entries for bike/rider weight and in future go with the lowest figure again

 

[Garz]

Also suprised what your Garmin is telling you. Check your weight and height inputs.
I take the Garmin figure and reduce it by a third as a fairly accurate calculation.

+1, this is what I too used to do.

 

[Mr Haematocrit]

What is making you reduce it by a third, why that value and not a half?

 

[Albert]

My Garmin 800 gives half the calorie count of my old 705 over identical rides. The 800 matches my Cateye watch pretty closely which under-reads the Gym equipment I use by around 10/15%..
I'd go with the Garmin 800's figure........ and maybe add 10%?.

 

[Ningishzidda]

If you are trying to lose weight by riding 30 mile rides, forget all the cals values and use 'will power'.

PS V for Vengedetta, have you performed a VO2 max test in a climatic chamber?

 

[Pedrosanchezo]

IME Garmin are way off on calorie count.

An example is yesterdays 40 mile ride. Half of it was intense riding and the other half at almost recovery pace - the point where i joined my brother for a social ride.
My Garmin 500 estimated 2700 calories over the 40! Strava estimated 1480, which is much more likely.
I do incorporate a fair bit of climbing in my rides but even then 2700 is a bit silly.

I don't count calories btw. I just check all stats at the end of a ride. Then give it one of these - - when i see Garmin's calorie count.

 

[gb155]

I want to play with a v02 test