Strava registers lower distance than TomTom MySports

renevdlee

Hi,

i am using a Runner 3 watch and overall my experience is very good. However, I use Strava as my main app and lately I notice that Strava often lists a lower distance than TomTom, greatly affecting my pace in a negative way. I know that each app may use its one algorithm to calculate distance, but I find it remarkable that Strava tends to decrease the distance at run races. I am basing my statements mainly on short twisty trail tracks with several laps.

Example today: Tomtom (9.2 km), strava (8.9 km) - 8 laps trail race
Example last weeks: Tomtom (8,97 km), strava (8.6 km) - 6 laps trail race

I think that differences of 3.2% are quite big. Do you have similar experiences with Strava?


I used to have previous models of the multisports where the deviations were not as big with strava. Do others have similar experiences and is there something I could do about it? I also tried to manually upload tcx / gpx files to strava, but the distance stays the same.

Thanks!

tfarabaugh

renevdlee wrote:

Hi,

i am using a Runner 3 watch and overall my experience is very good. However, I use Strava as my main app and lately I notice that Strava often lists a lower distance than TomTom, greatly affecting my pace in a negative way. I know that each app may use its one algorithm to calculate distance, but I find it remarkable that Strava tends to decrease the distance at run races. I am basing my statements mainly on short twisty trail tracks with several laps.

Example today: Tomtom (9.2 km), strava (8.9 km) - 8 laps trail race
Example last weeks: Tomtom (8,97 km), strava (8.6 km) - 6 laps trail race

I think that differences of 3.2% are quite big. Do you have similar experiences with Strava?


I used to have previous models of the multisports where the deviations were not as big with strava. Do others have similar experiences and is there something I could do about it? I also tried to manually upload tcx / gpx files to strava, but the distance stays the same.

Thanks!

This is a Strava issue that TT has been trying to resolve with Strava. Unless you are using a Garmin watch, Strava recalculates the data and comes up with its own distance, which it rounds down, rather than using what the watch says. They actually check the data and if it is marked as a Garmin product they use the watch data, otherwise they recalculate everything (and do it quite poorly). It is very annoying, I agree. I have actually been in touch with a TT developer and he has been working with Strava to try and get it right. Hopefully they can figure it out, we will just have to wait and see.

I hope this helps, please let me know if this answered your question. If it did, please mark it as a solution so others can look for it if they have the same question.

renevdlee

Thanks for your reply and explanation!

I was already afraid that this is a Strava problem. Hopefully Tomtom will do their utmost to lobby with Strava and get this solved. It just influences the results too much. I do find it strange that my friend (wearing the 1st generation of the multisport) does not have this problem.

Does this error affect the performance at Strava segments as well? Or does it mainly shorten the route distance?

tfarabaugh

renevdlee wrote:

Thanks for your reply and explanation!

I was already afraid that this is a Strava problem. Hopefully Tomtom will do their utmost to lobby with Strava and get this solved. It just influences the results too much. I do find it strange that my friend (wearing the 1st generation of the multisport) does not have this problem.

Does this error affect the performance at Strava segments as well? Or does it mainly shorten the route distance?

It seems to just short the overall distance. The only saving grace is they also factor out anything they consider stopped time even if you didn't stop the watch so you end up with a faster pace. It works fine on SportTracks, Garmin Connect and other sites, which match the watch, so it is definitely a Strava issue. Seriously aggravating and Strava does not seem to care because TomTom is such a small player in the market. If it was an issue with Garmin you know they would fix it in a second.

rawkinrich

I'm having the same problem with the Spark 3 and Strava. Completed a full and half marathon recently and achieved personal bests, only for Strava to round the activity down by .2 and .1 of a mile respectively.

Absolute wind-up!

rawkinrich

In other words - this issue hasn't been resolved.

tfarabaugh

If it is any consolation, my Garmin shortchanges my distance on every run!

rawkinrich

This is what Strava say to the short distance on the activity:

It looks like we found some sections of your file with bad data so we recalculated your activity's distance by blending the GPS and device distance together in order to correct those areas with bad GPS/device data. I reverted this change for you so your mileage and time should now more closely match that of your device.

The problem is, every long activity that's automatically export from TomTom MySports goes through the same scenario.

rawkinrich

And...

The issue at the moment looks like we have detected some data errors in the original files so our upload system automatically updates the distance to a combination of the distance data and gps data, unfortunately this can cause some inconsistencies.

rawkinrich

And now Strava blame TomTom: "It does look like the device recorded some errors, which is why we automatically switched over to the GPS data instead of the device distance. If this continues to happen, I would suggest resetting your TomTom device and ensuring it has the latest firmware installed."

Thoughts?