Fulmar, I did exactly the same thing when I first measured runs with Google Earth (measured lane 1 on a 400m track). And I came up with the same question regarding climbs and descents. Surely these can't be accounted for from a satellite perspective?
... ALTHOUGH: the altitude is constantly monitored as you plot your route. But the question still remains as to whether the software utilizes this information in the final calculation.

Does anyone know the answer to this?

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GONE RUNNING

A quick search says that they don't consider elevation in their distance measurement... How much it affects your run I guess depends on the duration and incline of hills on your route...

for example a slope measured at 1km as the crow flies with a 15% gradient (which would be quite a hill!) would measure on google maps as 1km, or 1000m... though in reality it would measure about 1107m for the runner.

I think for the majority of my runs it wouldn't make much difference to the total mileage, but for those who do very hilly runs it may!

Well, better this way than the other way round. At least I am not running less than I thought.
But like Richard exeplified, it can make a big difference when, for example, I measured (and ran) 19 miles over hilly terrain... Maybe I could add another mile to it...

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“To give anything less than your best is to sacrifice the gift.”

Measured my track using a measuring wheel at 570m and using Google Earth at about the same.

Google Earth works very well! Was a bit sceptical but like Fulmar checked Lane 1 at a local track and its spot on 400m!

I'm a Garmin 305 user now Strange thing is... if I upload the training sessions to motionbased (a third party piece of software) and Garmin Training Centre (the official software) I get slight discrepancies (sp?!) in the duration and distances measured?? Strangely though its motionbased that seems to match what was on the watch when I finished the workouts? Not enough of a problem for me to worry though, we're talking 1/100ths of a mile!

Seen on another forum today....

http://gizmodo.com/340267/garmin-for...-healthy-types

Screen looks a bit small...

Looks nice tho'

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