Distance sensitivity in running bests detection

[Giovanjane]

No GPS-device or running pod is 100 % accurate in measuring distance covered. Please add a sensitity margin to estimated running bests detection, such that efforts that are marginally shorter than the reference distances count as PB. 

It is really annoying if you PB in a, say, 5 km race or trial, ending up with a recorded distance of 4.99 km. This difference is well within the error margin of any GPS-watch or running pod, see Fellrnr's excellent research documentation: https://fellrnr.com/wiki/GPS_Accuracy-statistics. Yet, given the hard cutoff Strava is currently using, this effort is not detected as estimated 5 km run best. Even if we assume that 4.99 km is indeed the true distance covered, it is odd to assume that I could not have run the additional 10 meters at approximately the same speed.

Given the evidence, 2 % seems a reasonable and still very conservative sensitity margin, that is, any difference to the reference distance that falls within this margin should be ignored. For example, for the estimated 5 km best, any effort of 5. km x .98 = 4.90 km up to 5.00 km counts.

There are two methods to proceed: (1) Let the recorded time count as PB as it is. Or (2) take the average speed of the slightly short effort to scale the time linearly up. The difference between the two methods should be small (given the sensitivity margin is small), but in my opinion the second method is fairer. In any case, given that the running bests are "estimated" anyway, both should be okay.

[Soren]

Thanks for submitting your idea. It has been reviewed by our moderation team and is now open to voting.

[Giovanjane]

Come on guys, once again, I just did a 10K race on a measured (officially World Athletics sanctioned!!) course, watch says 9.98 km, hence not registered as a 10K Best Effort on Strava. The Best Effort feature is completely worthless in this form! I don’t see a valid reason why this fix should be subject to endless voting, it’s a quick fix that you guys owe to paying customers, especially after the flagrant price raise!

[Jan_Mantau]

@Giovanjane While it's understandably frustrating it isn't a bug on Strava side so it isn't a fix you ask for but a feature idea. And it's not even an easy one because the next person that runs 9,600 m in reality and recorded 9,800 m would get a new best effort for the complete 10,000 m if your 2 % idea would be implemented. The Best Efforts aren't worthless too as you can always run a few meters more to make sure that even the GPS acknowledges the 10,000 m. The time would be incorrect but there isn't a solution for that as long GPS in inaccurate.

[Giovanjane]

Where is the problem with that person running 9,600 in reality, recording 9,800, and getting a 10K Best Effort? Given the inherent inaccuracy in measurement, the Best Efforts must be taken as approximate anyway. And taken that way, they would still be valuable information to track, as efforts over a given distance +/- say 10% are physiologically and psychologically very very similar. I mean, it is highly implausible that a person running a 9.6K effort would not be able to continue 400 m at the same speed. And even if you favor a smaller margin than 2% (which is very conservative by the above argument), you cannot honestly claim that the Best Efforts are in any way useful to track progress if runs that are just a few meters short do not qualify. The suggestion to continue running after crossing the finish line in a race is ridiculous.

[Yakkity]

100% agree that this feature needs implementing. My 5k parkrun PB according to Strava is 26 seconds slower than my actual PB because on this occasion Strava recorded the run as 4.99km. I may have to resort to GPX editing to add the 'missing' 10 metres!