OS vs Strava
 

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[Closed] OS vs Strava

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I've just done a walk/run with both the OS Map app and Strava recording.

Both recorded the same distance but OS Maps has recorded 560m elevation gain and Strava only 480m. Any ideas on which is more accurate?

I'm aiming to reach the 3064m elevation done on the National 3 Peaks (limiting to an hour a day for lock down), so 80m a day will make quite a big difference.


 
Posted : 02/05/2020 1:25 pm
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They’re both just having an educated guess. Split the difference and use that


 
Posted : 02/05/2020 1:28 pm
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Good shout


 
Posted : 02/05/2020 1:31 pm
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If youre not using a proper barometric altimeter id say use strava, but use the correct elevation function. That should link it to the known mapped elevation and give you a pretty reliable answer.


 
Posted : 02/05/2020 2:44 pm
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I suspect the OS app has a more accurate DEM but, as above, if you want to be more sure then a barometric altimeter is what you need.


 
Posted : 02/05/2020 3:08 pm
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if you want to be more sure then a barometric altimeter is what you need.

They work for short duration's but are a bit rubbish over an hour or any distance IME.

As soon as the weather changes (i.e. the sun goes in/comes out) they go all over the place. My Garmin is programmed to calibrate itself at my house, the profile usually ends up with a cliff edge when it corrects by 50-100m as I get back to the start!

I think Strava uses USGS data? And presumably OS is using their own data, and neither app is relying on the GPS to triangulate an altitude, Strava definitely gives the option to correct the altitude so it uses the contours of the mapping rather than whatever your phone is telling it.

I'd go with the OS number, assuming it corrects it using the base map not relying on a barometric altimeter or triangulation.

It'll also get you to your target quicker!


 
Posted : 02/05/2020 3:32 pm
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It’ll also get you to your target quicker!

Winner!


 
Posted : 02/05/2020 3:37 pm
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Log onto Strava, click on your activity, click the link under Elevation, click 'Correct Elevation'. This uses Stravas basemap - their complied elevation data - to alter the readings rather than GPS or barometer data. Warning: Your Elevation might go down making your challenge harder!

How Strava calculates elevation

Strava Basemap info


 
Posted : 02/05/2020 4:00 pm
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Might need Premium to correct the elevation.

I've done a basic check on a paper OS Map and the route I did plotted out very close to the Strava figure, so I'm going to stick to that moving forward. Also I can link it to the Just Giving page and it provides more stats, but looks like an extra day will be needed!

Thanks for the ideas.


 
Posted : 02/05/2020 4:09 pm
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In my part of the world, correcting Strava elevation adds 20 odd % to the elevation.
My 55km midweek loop climbs (using spotheights on the map) from sea level to 450m twice, = to 350m once, total 1250m. Barometric measurement comes in consistently around 1350m, accounting for a bit of undulation in the climbs I guess.
If I upload to Strava and click correct elevation, I get an extra 300m or so 'free' climbing.

These are minor mountain roads with steep drop-offs either side. Whatever mapping Strava uses must have points that fall up or down the hillside.

Hillrunning, the % of free climbing is quite a bit higher.


 
Posted : 02/05/2020 4:12 pm

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