Strava Route Builder Elevation

[neilr]

Hi,

If i plan a route using the Strava route builder, it has always given an elevation figure for the route that is around 20-30% more than the figure shown when uploading my GPS data.

Now, clearly its not really that important but I was just wondering if there is anyone to knows if the Route Builder is accurate or simply has a different set of inaccuracies to my cheap GPS (Bryton 20).

Thanks!

[richardxjr]

Dunno but try exporting it from Strava, upload it to Bikehike to compare (the planner I use with accurate ascent/descent figures)

[wilbo83]

Isn't the route builder still in BETA mode? For that reason, I assume that it will have some inaccuracies. I use mapmyride to build routes, export the GPX file to my garmin and then upload the ride to strava after.

[Gren]

Not using the route builder part but Strava never agrees with my gps. When using my old Edge 200 it used to remove around 25-20% of the climbing from any ride. I'm assuming this was when comparing the gps to its own maps.

Now I've upgraded to an Edge 510 it actually keeps the gps stats and now my newer but identical rides show around 25% more climbing than they used to on Strava

[richardxjr]

Gren's correct.

Edge 200 & phones don't have a barometric altimeter unlike 500/800 etc, so Strava ignores any of your altitude data and uses it's own, from it's own mapping. Which appears to be less generous than that suggested by Garmins own data.

https://strava.zendesk.com/entries/20965883-Elevat...

Barometric altimeters can be affected by weather and other factors, so at the end of the day, nothing is terribly accurate. Except that if this year you change GPS and find you've climbed 25% more, you haven't really

[PeteSV]

So, on Monday I bought an Edge 200, hoping to make my recording more accurate. I went for an hours ride last night to test out the new Garmin. I recorded the ride as normal on my phone with Strava, and also with Garmin and then dropped it into Strava. The elevation captured on Strava via my phone was 1538ft and when the Garmin data was dropped into Strava that was 1358ft. So which is correct?

Also to note, my milage was capured at 12.8, versus 12.3 via the Garmin. Looking at the maps side by side afterwards the Garmin appears to have captured less accurately withlots of corners cut off etc.

[richardxjr]

The other thing about the 200 is that it only records a routepoint every 5s instead of 1s, so you get a more jaggedy track, particularly off road.

As to which is more accurate, flip a coin.

It's all a bit unfair when it comes to really important things like PH Strava leaderboards though

[Gruffy]

I read somewhere that Strava's elevation data uses 30m square grids, so a bit low-resolution. Throw in some error margins for location precision and a low position marker frequency and you get the discrepancies we see.

It's a bit disheartening if you're chasing numbers but it's best to step back and look at wider trends which, over a large chunk of data, cancel out the inaccuracy.

I'm keen to find the optimum solution before I tackle an Everest though!

[richardxjr]

Elevation is all fked up on this Strava nonsense

I was just looking at a friends track ... I know the route well ... hmm 33k & 335m sounds far too high. Further investigation, Garmin 810 - so barometric ie should be accurate yeah, well accurate enough for Strava to accept ... look at the elev graph, fk me it's all underground! All under 0m elev, what a load of cock.

OSM route shows correct elev between +1 and +35m and a much more accurate to me total of 218m.


Strava claim to use OSM topo data for non barometric or corrected elev, but my own tracks and routes don't tally (Strava to all other OSM based routing programs).

So it seems all Strava have to do is actually use the OSM data that they claim to use and automatically elevation correct to this 'universal' topo data every uploaded track for a level playing field.

[afrochicken]

richardxjr said:

barometric ie should be accurate yeah

I'm not so sure. I have seen my Garmin 510 tell me my altitude was dropping while I was climbing

If I use the elevation correction on the Garmin Connect site, it approximately agrees with the elevation that Strava calculates using the Strava elevation correction

Just for consistency I always use the Strava elevation correction

[richardxjr]

.*should* as my mate's example above.

afrochicken said:

If I use the elevation correction on the Garmin Connect site, it approximately agrees with the elevation that Strava calculates using the Strava elevation correction

This is the issue. Take that track and trace it out in another OSM application (such as bikehike.co.uk) and you'll see a difference. Strava corrected data will be a fair bit out from the OSM topo elevation data that they claim to use.


Strava should auto correct everything to the same dataset. It's bonkers. Elevation gain is hardly minor issue when it comes to cycling data.

Edited by richardxjr on Thursday 8th January 12:04

[Gren]

richardxjr said:

The other thing about the 200 is that it only records a routepoint every 5s instead of 1s, so you get a more jaggedy track, particularly off road.

As to which is more accurate, flip a coin.

It's all a bit unfair when it comes to really important things like PH Strava leaderboards though

On the positive side, on 3 different rides my 510 and old 200 (on wife's bike ) have recorded almost identical total distances over 25 mile mtb rides. When I say almost identical, I mean 0.02 miles out. So for recording distances, even with it's 'chopped off corners' the 200 seems okay.

The images on Strava though do tell their own stories and I'm sure my segment times will be more consistent. There's been times when I got home thinking I'd scored a PR only to be 10-20 seconds slower on a 4 minute trail.

[broster]

If you upload your data to garmin connect it will correct the altitude and then you can sync it to strava automatically.

[richardxjr]

broster said:

If you upload your data to garmin connect it will correct the altitude and then you can sync it to strava automatically.

Must be magic but looks better. I uploaded a fresh track to Strava via Garmin connect, 25.9km / 569m on Strava. Took the same file off my Garmin and uploaded it to Bikehike (that I trust), 25.94km / 566m.

Then I traced out the same route manually on to Bikehike 26.21km / 579m

(non barometric altimeter on my Garmin)

[okgo]

You can correct it on strava, just click n the question mark next to the elev.

Why anyone gives a flying one about elevation I have no idea.

[richardxjr]

Correction only available for barometric altitude. Yes, why would anybody be interested in climbing stats.

[okgo]

richardxjr said:

Correction only available for barometric altitude. Yes, why would anybody be interested in climbing stats.

To the nearest hundred ft or whatever everyone is moaning about.

Average speed I can just about understand, but strava taking 250ft of your 3000ft ride, who cares.

[Gruffy]

I lose up to 40% of my elevation. That's a big margin of error. It bothers me because I'm keen to learn what 4,000m of climbing is like but I don't know if I've done 2,500m or 4,000m, so I've no idea how prepared I am for a ride which I know is 4,000m.

[ALawson]

One ride in Tenerife Garmin 2500m, Strava 2999m.

Having looked at maps we think Strava was closer to the real value.