GPS watch calories burned?

[kurt909]

I've started getting back into fitness and got the bike out again. I bought a gps watch just as a gift to myself.

Did a short ride this morning and these are the results. Sorry for noobness.

Basically I'm wondering how accurate the calories burned are. I know gym equipment Is useless so I'm thinking this could be the same?

Anyone else use them and have good experience?

 

[T.M.H.N.E.T]

Not very.

 

[Saluki]

My garmin tells me calories burned. I am not sure about the accuracy but I use it as a guide as to whether or not I can have some cake.

 

[Soltydog]

Not very accurate at all. I have a Garmin edge & also occasionally use Strava app, On one ride the Garmin showed 60% more calories & both have the same data.
There's many factors that will affect the figure that will not be taken into account, ie wind speed & direction probably the main ones

 

[screenman]

I always half the number as I am in weight losing mode.

 

[Saluki]

I use a site called Sparkpeople, where I log rides, walking, eating etc and the Garmin is only about 10% over the Sparkpeople estimates.

 

[ianrauk]

it's an arbitrary figure

 

[michaelcycle]

Not very.

Pretty much. It's an estimate based on an algorithm using the data you entered into your watch on setup.

A more accurate estimate could be gained by using your heart rate strap for monitoring and particularly if your watch allows you to enter resting heart rate, max heart rate, VO2 max, weight, age and gender (as well as assuming you know the heart rate / VO2 figures with some degree of accuracy.) This is because of the relationship between oxygen uptake / heart rate / energy expenditure.

Incidentally in some circumstances the gym machine readouts can be pretty good but it depends on the circumstances really.

Long story short is it's not worth worrying about.

 

[guitarpete247]

I'd have thought you should take into account the weight of bike and aerodynamics, rolling resistence of tyres, bearing quality of wheels etc. It'll all have a little effect. So it's only a best guesstimation.
But I use mine to decide if I can have a bottle of wine that night and not worry about it.

 

[uclown2002]

I reckon 40 calories per mile is as good as any other guess.

 

[sannesley]

I was wondering the same with my Garmin watch and calorie reports for a ride but you guys have cleared it up a little for me.

 

[Joshua Plumtree]

I always work on the belief that it's between 300-500 per hour. So five hours in the saddle equates to one whole carrot cake. Depending on level of effort and cake mixture recipe naturally!

 

[kurt909]

I guess it doesnt matter how much, its still better than sitting watching TV all day..

 

[ushills]

For what it's worth, Strava seems to underestimate a lot compared to a polar HRM (correctly set up), Garmin seem slightly over a polar HRM.

 

[blazed]

If I did 12 miles with endomondo it would tell me I burned 1000+ calories. With my mio cyclo gps about 500 calories. I like to track statistics it's the only way of pushing yourself harder and improving, but calories burned is one you're never gonna be able to track accurately. I'd forget about it.