Analysis of Alyx Ulbrich’s Decaman USA Data Strengthens Case For Disqualication

After news of her disqualification was made public, a defiant Alyx Ulbrich posted, "If You Have Questions, Check My Strava".



Alyx Ulbrich was disqualified from The Decaman USA race after she was observed skipping a lap. Alyx conceded that she must have missed the lap, but claims it was an accident.

I did check her Strava in painstaking detail. I received the timing data from the race and matched up her GPS data lap by lap. Before I get into that detail, let’s summarize the events leading up to the run portion of the event.

For the purposes of full disclosure, here is a link to her complete timing data. Note that laps marked with “M” under the port column were manual entries. These could made be made for a variety of reasons. If a runner didn’t register while crossing a mat, they may have added a lap manually at a later point. They also adjusted the lap distance after lap 40.

Alyx’s Decaman laps

Summary of Events – Alyx Ulbrich – Decaman USA

From the beginning of the race there was controversy regarding Alyx. Alyx felt that the counters  didn’t credit her with the proper amount of laps for the swim. She based this on a discrepancy between her official distance and with the distance shown on her Garmin. During the swim portion of the race, she aired these concerns on Strava.

This was the start of a trend where Alyx would post concerns publicly and the first hint that she felt as if she was being treated unfairly as an ‘outsider’

The race had counters at the pool, keeping track of the laps. Garmin data is known to deliver questionable accuracy for indoor swims. If the counters missed a few miles of the swim that would be the equivalent of 90 or so laps.

Alyx finished the swim 13th out of 15 competitors in a time of 19:10:01.


Alyx’s frustration coninued as evidenced by the post above.

At one point, according to a friend of Alyx’s, she was warned for drafting. I can only assume that the above post was a reaction to that. Alex’s Instagram also indicated that she had witnessed drafting in the race. I have no evidence one way or another as to whether Alyx or anyone else was illegally drafting.

Alyx says that she was not drafting, and it was relayed to me that she felt singled out for riding side by side with another rider.

She finished the bike in 9th place out of 10 remaining competitors.

I mentioned the lead up to the run to provide context. Alyx put forth her opinion that she was targeted because she was an outsider. I’ve received messages from people who spent time with Alyx that echoed with this sentiment. On the flip side, I have received messages from athletes saying that they were initially very welcoming and supportive of Alyx.  In the end, the atmosphere is irrelevant to the key question as to whether Alyx intentionally skipped laps during the 262 mile run.

The Run

Alyx’s frustration continued.

The race had to enforce the no headphones rule since the run was moved to a shared course. I have confirmed that this rule was enforced for everyone and that Alyx was not singled out in this instance.

For reference, below is a map of the buildings near the timing area. The timing mat is adjacent to the bath at the end of the blue line.

Summary of Alyx’s Strava Data

The run portion of Decaman consisted of 249 1.051 mile laps for a total of 262 miles.

Alyx ran 10 penalty laps (which I confirmed through her Strava), and admits to accidently missing a single lap. If Alex only missed that single lap, she would have run 258 laps.

GPS shows that Alex hit the turnaround point 242 times.

This leaves 16 laps unaccounted for.

I will concede that some of those laps could be due to GPS issues – forgetting the watch or battery dying.

I took a detailed look into all of her Strava entries and the statements of those that say they saw Alex cheat. I was looking for some evidence that either corroborated the witness statements, or that would vindicate Alyx.

Analysis of Questionable Laps

Multiple witnesses claimed to have seen Alyx skipping laps. They claim that she would leave the course after completing a lap, leave the course for and return to the timing area and cross the timing mat to register a lap without actually running that lap. A couple of these statements were specific enough that I could pinpoint the laps where this behavior was alleged to have occurred.

Timer: Stacy Martinez:

Tuesday: November 13th:

I see Alyx Ulbrich pass in front of my timing tent, instantly I alert her. “I did not hear a DING.” I let her know she needs to go back through. She hesitated for a second, so I told her again that she did not register. She then turned and went back and made the DING sound. She was with her crewmember at this passing. I told her I was going check her data and make sure that the ding did register a lap for her, and for her to carry on with her next lap. She hesitated and motioned in a way to not worry about it. She Stated {I’m sure it’s all ok.} (Paraphrasing, as I don’t know exact words to place in quotes)

I pulled up her lap details and it hit me when I saw the data. The last lap was for over 2 hours; she had just come from the food tent area, which meant she just came off a long break. She should not have crossed timing mat again because she only went to tent and back to mat. 

This was my mistake I realized. I kept going over what had happened and how she had interacted with me during this specific event.

My head questioned; did she know she was not supposed to cross matt and did it anyways because I told her too? Did her mind at that point justify getting the extra lap because she knew I made a mistake?

I was able to determine that this happened on lap 8 of Alyx’s run:

Lap 7 completed – 3:23:08 PM. Confirmed by Strava data.
Lap 8 completed – 6:10:10 PM. Total time of 2:47:02.

Alyx’s Strava did not have any run data between 3:23 PM and 6:10 PM.

Her previous Strava entry ended at 3:23 PM. Her next entry started at 6:09 PM, just prior to when she registered lap 8. This would be the start of a pattern that where Alyx did not record her laps immediately following her breaks.

Later that night my main timing relief came. … and I was showing her what all was entailed and how to answer questions for athletes and their crew. It was at this time that Alyx came from food tent again. I watched her and she crossed mat and it made DING sound.

I decided to be safe I would be extra watchful of all her future laps and keep an eye to see if she does this again. I at that time made a note on clipboard that read “Watch Alyx.” I did this so I could tell the next timer what I did and to make sure it was an accident on her part. I was sure hoping it was an accident.

I did not stop her right then, I did however pull up her lap data immediately and saw a long break had just transpired of over an hour. Yes she did it exactly as the previous time. Yet this time I did not tell her to do it.

Since I knew for sure what happened this time I grabbed her crewmember and told him what happened not in an accusatory way, just informative. I explained that when she comes back to main timing tent to not cross mat to pay back the double DING.

The reason for this is because there is no way to manually subtract a lap in software it can only be paid back in this manner.

The lap that Stact was referring to was lap 21. It also does not appear that Alyx skipped the timing mat the next time around as requested.

Lap 20 completed – 8:51:25 PM (confirmed by Strava),
Lap 21 completed – 9:56:14 PM Total Time of 1:04:49.

She again has a gap in her Strava entries. She stopped recording after finishing lap 20, and started recording again at 9:57 PM. She has nothing recorded that would show that she was on the course during lap 21.


Laps 37 and Lap 40

There were two more laps that really stood out to me when looking at her Strava. Laps 37 and 40.

Both of these laps were not recorded on her Strava. The Flybys raise additional questions based on her movements just prior to finishing the laps.

For lap 37 it appears she started behind the timing mat, and moved around a bit for 5 minutes before crossing the timing mat and continuing with her run.

For lap 40, it is clear that she approached the timing mat from the area where the bunkhouses are located. The path shown would be consistent with the observations of the witnesses that claimed that Alex would cross the timing mat directly from the bunkhouse or kitchen area in order to be credited with laps that she did not run. Below is video and my explanation of what is seen regarding lap 40.

Participant: David Clamp

I had finished my race and had just been told about the suspicions re Alyx. I decided to keep watch myself ( and didn’t have to wait long !!!!) and spotted an infringement as soon she finished her next lap. Alyx crossed the finish line and I saw her go to the timing position and heard her ‘beep’. I started my stopwatch and watched her go to the bunkhouse . I saw her come out of the bunkhouse after 36-38 mins on my watch and saw her go over to the timing point and registered a further ‘beep’ for a completed lap..

This was the same lap that led to her being confronted by The race director, and which Alyx later conceded that she may have made a mistake.

Consistent with the other laps where she was suspected of having skipped, she has no Strava data to show that she completed the lap.

This lap was lap 175.

She finished lap 174 at 7:42:33 PM on 11/17 and she stopped her GPS at the same time. She finished lap 175 at 8:21:03 PM, she started her GPS at 8:19 PM.

It was after this lap that she was confronted by race officials. The race director also witnessed her behavior. She was initially disqualified. According to the race director, he said she could do whatever she wanted, but that she was disqualified. The following day Alyx said she would do whatever it takes to earn an official finish. She said that she would do 1-50 more laps to be an official finisher. Under ‘this duress’ the Race Director reluctantly agreed to 10 more laps as a penalty. Race officials interpreted Alyx’s pleadings as an admission of guilt.

Later that evening, he felt that the decision to allow her to remain in the results was mistake and decided that he would uphold the disqualification.

A Clear Pattern

There was a very clear pattern from November 13th through November 15. During this time she had 9 laps of over 1 hour. For 8 of these 9 laps, she did not record her GPS data. There were other gaps as well. But this pattern was clearly repeated for two consecutive days. If there was a legitimate reason for this pattern it should be able to have been quickly explained. There were other similar gaps. There were 12 similar gaps where 1 lap was not recorded. There was also one instance where 2 consecutive laps were missed.

Alyx’s Explanation

I asked Alyx about this pattern multiple times and did not get an answer that I could rationalize.

She said that she would go to her tent when she took her breaks prior to crossing the timing mat and registering a completed lap.

This would seem somewhat plausible since she would reach her tent prior to coming to the timing area. However, if this were the case, I would expect to see some GPS evidence of this.

For example: Lap 27. 6:51:56 lap time. No GPS evidence

Alyx says that she would go to her tent and take a nap prior to entering the timing area which would explain why we don’t see a GPS track for the entire lap – assuming she stopped her GPS when she approached the tent.

However, if this were the case, I would expect that her GPS track from the prior entry would show her starting lap 27, and that she would shut it down when she approached her tent.

In no case does Alyx’s GPS track show her stopping prior to the timing area. I would expect the GPS tracks would end at her tent. I did not find a single case where, leading up to a break, that showed Alyx approaching her tent prior to reaching the timing mat.

There is no indication on any of the other missed laps that she went to her tent prior to registering a lap.


I have heard from other athletes, volunteers and support staff that I did not quote in here. Other athletes posted their observations on social media. I spoke to and messaged with supporters of Alyx as well as those that say they witnessed Alyx intentionally skip laps.

The supporters of Alyx mentioned issues with the race, and the alleged unfair treatment of Alyx. I don’t think it’s in dispute that the race suffered from a lack of volunteers, and this strained the staff over the 13 days of the event. They changed the run course due to bad weather and out of concern for the runners. There was no timing mat at the turnaround of the run course. Had there been a timing mat, it would have been simple to see if someone skipped a loop.

What none of her supporters were able to show me was any evidence or reasonable explanation regarding the key issue – the allegation that Alyx skipped laps.

As I pointed out repeatedly, Alyx put her Strava up as the piece of the puzzle that would vindicate her. The Strava data simply does not do that.

In the instances where witnesses gave information that tied to specific missed laps there is no Strava data. The witnesses all said that she would skip laps by crossing the timing area from her tent or the bunkhouse area following breaks. Nearly all of the gaps in her Strava data is for the laps immediately following her breaks.

In short, the Strava data did not clear Alyx of these cheating allegations, it served to corroborate the stories and strengthen the case against Alyx.


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  1. Good work Derek. Like almost all other cases of cheating, the attempted cover-up makes it worse. The data doesn’t lie. I wish these social media lovers would just admit they were wrong and move on.

  2. Thank you Derek- the ultra community is a tight one- but is welcoming of persons who wish to truly be a member of the community. Alyx appears to have been in this for one reason only- self bragging. Not for the love of the sport. Thank you for your unbiased examination of this issue and for hearing all sides. I help at this event in Virginia and these are great people and athletes. To have alyx constantly berate this community is a true indication of her motives. so sad.. i do wish her well in life.

  3. I don’t know about Decaman, but typically in draft-illegal races, riding side-by-side is also illegal. Once you enter someone’s draft zone, you have to complete the pass. So unless this is explicitly not the case at Decaman, then they were right to warn or penalize her for riding side-by-side

    • Tom, some ultra-distance events allow for short periods of side-by-side riding. I’ve raced both a 12 hour and 500 mile “time trail” races that allowed for up to 15 minutes (I think it was every 4 hours, it’s been years). Shorter races like 140 mile triathlons do have the “you must pass” rule though. I’m not sure what DecaMan allows though.

      • Decaman (and most ultra triathlons like it) do allow side-by-side riding, and tend to be much less strict than most “standard” distance tris. Still no riding somebody’s wheel, or clear, intentional drafting allowed.

      • I was in timing tent when Steve Kirby (one of the RD’s)stopped her and warned her. This is what I heard.

        “I need y’all to quit riding side by side.”
        He explained that it was ok to chat a little but he informed her and a guy that they had been together side by side for three loops. That would be 21 miles.

        He was not agressive. She started dropping F Bombs and for the next 3-4 times she came through timing mat I would hear her cussing and grumbling about this one conversation.

        • Stacy, thanks for the update.

          Three loops of side by side would have been (at least to me) a major mental boost. One of the hardest things in the ultra world is being alone with yourself when your mental game starts to falter. Having someone nearby when that happens can save a race.

  4. It seems the volunteer accidentally and unintentionally gave her the idea on how to cheat. By getting a free lap every time she took a break.

    • That’s probably where she’s getting the admitting it was an “accident” on one lap. The first one really was an accident (Sort of). However if she knew that she shouldn’t cross the mat she should have told the volunteer that. She would have known whether or not she needed to cross the mat.

    • Yes I did unfortunately. This was my feelings the whole time aferwards. I felt like it was somehow my fault for what she did. At the end of the day, I had to forgive myself for my mistake and let her take responsibility.

      This race being small has always been about self achievement and personal integrity.

      • Don’t beat yourself up over it. She could have told you that she was heading back out again and shouldn’t go over. She didn’t she chose to go over the mat when she shouldn’t have and then chose to do it several more times. That’s not your fault.

  5. I don’t understand how someone who is actually capable of doing what SHE DID DO, still goes and cheats themselves (and others) by shorting the race by a – comparatively – meager 10 or 20 laps. It’s pathological. It’s also antithetical to the spirit of racing.

    I compare this to what the crazies (Johan and Courtney) did at Laz’s Big’s Backyard race. Pushing themselves to ridiculous new heights. They would never dream of cheating because their accomplishment would be meaningless in doing so.

  6. I’m finding this one pretty unpersuasive. Crazy set-up to begin with – one mat, near a lot of other activity, people leaving and entering the course, and everyone having to keep track of 249 laps. I often get confused when I’m running 16 X 400m! (“Was that #12, or #13?) Then you have the timer telling her that she has to cross the mat to start a new lap. Of course she would follow those directions. And if I’d run 100+ miles and taken a break of a half hour or more, I wouldn’t necessarily remember if I had crossed the mat when I came off or whether I had to cross it again. No connection to the race or individual, just an observer.

    • You would probably use some sort of aid to help yourself keep track of things. As an observer I would say “one time could be an accident, two times not likely, three times and you are looking at a cheater for sure”. Even if she didn’t have any intention and the time-teller made her do it the first time, which I find somewhat unlikely, it doesn’t excuse the following cheats.

      If you go to a candystore and the clerk gives you a free cookie, i doesn’t mean that you can just keep taking free cookies every time you enter the store.

    • I think the description of the witness is pretty convincing, the initial false lap was accidental but once she had the idea then repeated

  7. I’ve never run anything remotely like this, but it seems like there’d be some sort of unambiguous guideline that you either cross the mat coming into camp or leaving camp. Does anyone know how the stop/camp would work? I sort of thought that events of this magnitude had officials and medical personnel at the stops checking folks rather than participants just dropping in, taking a nap, and eating a gel.

  8. I am not defending her in anyway, but I have never had my Garmin over count my swim distance. When ever there is a mistake it under counts. How do you explain that?

    • My Garmin horribly overestimates my swim distance. I believe this is caused by going relatively slowly so the number of data points recorded is high and the error in each one adds distance.

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