Thursday, June 30, 2016

Rob Young Uploads Driving GPS File, Deletes It

A file uploaded to a Strava account under Rob Young's partner's name, which was subsequently and rapidly deleted, had been reconstructed by users over at LetsRun.  The file shows a 1:56 mile and suggests the RV was forced to travel too fast due to a lane closure.

Acceleration at end of lane closure section, followed by attempted backtrack


Strava Sandbox


On Friday June 24 when Rob Young began trickling out his Strava uploads, some astute individuals at LetsRun.com noticed there were also uploads to an account under his partner's name.  Most likely, Rob was checking how the files looked here before uploading to his own account.  He since indicated he figured out how to make activities private, and emptied out the other account.  Here's a screenshot of one particular activity uploaded to that account, taken 6/24/16 10:15AM PDT:

Source: https://www.strava.com/athletes/15812258 (now empty)

Reconstituting the File


LetsRun forum members scrambled to download the raw data, with a Strava Premium member helping out.  Unfortunately, GPX downloads from Strava using this feature contain only the GPS points as a course.  There is no specific time stamp information, only a series of longitudes and latitudes.  On first pass, such a file seems useless.  However, not to be outdone, forum members devised a way to accurately regenerate the file.

The key observation is that the TomTom watches Rob use record at 1 second intervals:

Source: http://www.dcrainmaker.com/2015/11/tomtom-spark-review.html

The activity we're interested in has an elapsed time of 5:06:21 according to Strava - that's 18,381 seconds.  To make an activity of x seconds elapsed time, we'd need x+1 points spaced one second apart.  Convince yourself with the simplest example - a 1 second activity would need 2 points.  So how many time-less points are in the downloaded file?

GoldenCheetah Edit function - 18,382 points/seconds

There are 18,382 data points in the original GPX file.  OK, perfect, so the watch must have been left running the whole time and generated one point every second for 5 hours, 6 minutes, 21 seconds.  All that's left is to pick a start time, which can be accurately estimated from Rob's RV tracker data, and write a script to add incrementing time stamps to the GPX file.  The LetsRun "tech department" did just that, and the result is on an alternate Strava account.

Analyzing the File


Strava estimates a 3:44 mile, which is pretty damning, but it appears they disallow PRs better than world records, and the real story is even worse.  Here are some best efforts calculated with GoldenCheetah:

GoldenCheetah - Top two 1 mile efforts, top two 2 mile efforts

Rob has done one mile of this activity in 1:56 and another in 5:41.  His best 2-mile pace was 4:23min/mi.

Let's take a closer look at the really fast section:

Fastest mile
Strava Animation
Huh, interesting.  Looks like they zoom it at high speed from the left, then backtrack a bit at a slower pace before continuing on.


Providing the Context


This is pretty bizarre GPS behavior, and I set out to figure out why this might have happened.  I looked at Google Streetview for this fast section, curious what I'd find.

Site of the sub-2 mile pace

Interestingly, it goes down to one lane for construction.  The imagery is from April 2015, so it may not be valid anymore, but an RV forced to speed up by traffic that cannot pass makes good sense and led me to check the current road status.  The Arizona Department of Transportation site shows road conditions and active construction areas.  It appears that while the exact conditions from Google no longer exist - there is in fact still a lane closure at that area (this time it's the left lane).

AZ DOT Lane Closure - mile marker 81.0 to 84.0

The closure starts where the East and West directions of the freeway split, and goes on for 3.0 miles, which is the exact site of the backtracking.

The Final Narrative


Follow along with the graphic below.  Here's what I think happened.  From left to right:

  • The RV is cruising along at a steady speed, with Rob inside, ticking away the "miles".
  • They take a break while approaching the lane closure, and soon after entering this zone, they take another break.  Maybe they'e spooked to be driving so slow in the only available lane with narrow shoulders and they are debating what to do... who knows.  But they continue on.
  • A vehicle approaches, a long haul trucker maybe, or a line of vehicles amass.  People are upset.  It's dangerous and inconsiderate, and they can't keep doing a few miles per hour in the only lane available.   They accelerate, reaching high speeds towards the end of the lane closure zone.  They close the last mile of the zone in 1:56, and pull over as soon as the other lane opens at mile marker 84.0 (their mile 11.7).
  • They decide that was too fast, and Rob gets out to backtrack and get some legit GPS coverage.  The backtrack is not nearly far enough, but I think that's to be expected.  If you were driving along a dark rural highway and someone stopped you and said, "run back to where you were a minute ago", I'd venture a guess that most people would end up short.
  • They continue some intermittent running after they've been spooked by this incident, but then they go back to steady RV cruising.

Sequence of Events

Alternative Explanations


Certainly, one could argue that this recording was just a mistake - the watch was left on in the RV.  It was deleted innocently since Rob realized it wasn't a run.  Maybe Rob was really running, and the RV sped away from him.  They backtracked to meet him.  I acknowledge the possibility of other explanations, however the facts remain:

  • Rob has no other run uploaded to account for this section
  • The backtrack was almost certainly done by a person.  The track goes on the other side of the guardrail, and an RV going in reverse at 2-3mph into the only available lane is preposterous.  Therefore, the GPS watch was likely on the wrist of someone in the RV.  That's hardly a mistake, since either that's Rob in the RV, or another crew member inexplicably recording miles on the watch.  A GPS watch left on accidentally deep inside an RV probably wouldn't even have satellite reception.
  • The backtrack takes 2:12 until continuing forward again.  A 1:56 mile plus 2:12 gives a left-behind Rob Young only 4:08 to catch up to the RV in one mile.  Highly unlikely...

While there are other possibilities, there is no corroborating run for this section and the GPS watch was intentionally operated by someone in RV, facts that are very damaging to Rob Young's claims.

Conclusion


Rob Young uploaded, and then deleted, a file that has an impossible 1:56 mile within it.  Further analysis and correlation with road conditions suggests that the high speed was due to an unsafe situation with a single lane construction area.  This supports the notion that the Rob Young and his GPS watch were really just traveling along the RV.

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