As It Happens

Online sleuth uses fitness tracker data to bust half-marathon cheater

As It Happens talks to an Ohio man who busted a cheating half-marathon medallist using fitness tracker data and high-resolution images.
An online sleuth has busted a cheater in a half-marathon using GPS data and photographic evidence. (Pavel1964/Shutterstock )

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A popular runner and fitness writer has been stripped of her second-place medal for last weekend's Fort Lauderdale Half Marathon thanks to the vigilant detective work of an amateur online sleuth.

Jane Seo, 24, who writes about food, fitness and running for the Huffington Post, has been retroactively expelled from the Fort Lauderdale, Fla., race and kicked off her racing team, the Dashing Whippets, after it was revealed she had skipped 2.4 kilometres of the race.

And it's all because of a detailed investigation published by Ohio's Derek Murphy on his blog Marathon Investigation, which he runs in his spare time.

Jane Seo has been retroactively disqualified from the Fort Lauderdale Half Marathon after a blogger discovered she had skipped part of the race. (@JaneSeo14/Twitter)

"I don't watch much TV, I don't play on the computer much besides doing this, and I think it helps clean up the sport a little bit and it does help people out," Murphy told As It Happens guest host Helen Mann.

It started when the official race timer noticed a fishy detail in Seo's official timing, the Miami New Times reports.

According to her official marathon race tracking chip, Seo's pace increased during the last 11 kilometres of the race. Runners usually slow down during the final leg due to exhaustion, especially in hot climates like Florida.

I think it helps clean up the sport a little bit and it does help people out.- Derek Murphy, Marathon Investigation 

Still, Seo was able to convince the marathon director everything was on the up and up. That's when someone tipped off Murphy, a man known for busting cheaters trying to qualify for the Boston Marathon.

"If somebody were to cheat in a qualifying race to run Boston, that means somebody's being left out who deserves a spot," Murphy said.

Covering her tracks

Murphy brought up Seo's profile on Strava, a social media app where runners and cyclists post their times, and noticed she had uploaded her Fort Lauderdale numbers manually rather than letting the app pull her GPS data. 

"She had literally hundreds of other entries and none of them were manual, so that was her only manual entry," he said. 

Later in the day, she uploaded more info to Strava, including her path and cadence, a.k.a., steps per minute. Murphy noticed her cadence was more in line with cycling than running. What's more, the data showed she'd completed the track in the afternoon, after the race was over.

Murphy determined from Seo's race map on Strava that she completed the track after the race was over. (Marathon Investigation)

Based on that, Murphy said it was "fairly obvious" that Seo went back to the track after the race and completed it on a bike, which he described as "highly unusual."

Photographic evidence

But the smoking gun came from official marathon photos of Seo. 

"I decided to look at the photo to see if she was actually wearing a GPS watch. That would explain the manual entry, you know, if you'd left the watch at the hotel," he said.

"And I did notice that she had a GPS watch on and I could see the face of the watch in the photo, so I purchased a high resolution copy of that photo and was able to zoom in on it."

It showed 11.65 miles — about 1.5 miles less than it should have been.

"That's when it became indisputable that she cut the course."

Derek Murphy zoomed in on Seo's GPS tracker to find out how much ground she'd actually covered. (Marathon Investigations)

Murphy told As It Happens he doesn't always publicly out the cheaters he catches, but felt it was warranted in this case, because Seo benefits from her runs through her writing, social media followers, sponsorships and membership in an elite running club.

When the truth was revealed, Seo apologized on Instagram before deleting her account altogether. The Washington Post saved a screenshot of the apology.

"I wasn't feeling well so I CUT THE COURSE and headed to the finish line. I got swept away in the moment and pretended I ran the entire course, when in fact I CHEATED and should have DISQUALIFIED myself," she wrote.

"What an idiot I was!"


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