Jane Seo, 24, was disqualified on Sunday night after a race analyst, Derek Murphy, realized a picture of her watch did not match the total amount of miles included in the race.
Murphy found a photo of Seo after just having crossed the finish line, smiling with her second-place medal, he said in his analysis site, Marathoninvestigation.com.
He then zoomed into the picture to see Seo's Garmin GPS watch had been missing miles.
The 24-year-old had a total of 11.65 miles with a time of one hour, 22 minutes and seven seconds. About one and half miles were cut from her run which should have totaled 13.1 miles, Murphy said.
Seo, who was a writer at the Huffington Post, came clean about cheating on her Instagram account and even admitted to making up the missing miles on her bike after the race.
'I made a HORRIBLE choice at the Ft. Lauderdale Half Marathon on Sunday, February 20. I wasn't feeling well so I CUT THE COURSE and headed to the finish line,' she said.
Seo admitted to pretending to run the entire course and acknowledged she should have disqualified herself.
She added: 'Even worse, not only did I steal the award from the true, well-deserved runners/finishers, but also proceeded to BIKE the course afterward with my GPS watch to cover my wrong doings. What an idiot I was!
'As I admit to my foolishness, I am extremely ashamed. I sincerely [apologize] for bringing negativity out of the running community that I truly admire and respect. I take full credit for this mistake without any excuses and will face the consequences. I am so sorry, everyone.'
After the race Seo logged data into Strava, a mobile app for runners, which did not include any GPS data, Murphy wrote.
She later covered her tracks by cycling the distance and submitted another entry that showed she completed the race. Seo has since deleted her Instagram.
Murphy explained that although Seo admitted to cheating, it was not until the evidence was brought to her attention.
He said: 'She had the opportunity to come clean after crossing the finish line. Instead, she doubled down with the deceit. She approached race officials and other runners defending her time.
'They did not approach her. She proactively went to them. She did attend the awards ceremony to collect her 2nd place award.'
Murphy also made note of Seo's claims of feeling unwell during the race. The investigator said the woman did not look distressed in her finish line photos and she still had the energy to bike 13.1 miles that afternoon to cover up her tracks.
Fort Lauderdale A1A Marathon & Half Marathon officials addressed the incident in a Facebook post saying they have spoken to Jane and accepted her apology.
'I have spoken with Jane Seo and she apologized to me, which I gladly accepted. I took the time to talk and console her. She is hurting. She accepts the consequences, and I finally got her to laugh after a few minutes. Life is about second chances. I have moved on, and suggest the same for everyone,' the post said.
Seo's writer profile says she graduated from Harvard University in 2014. In 2015, the blogger wrote an article titled:How I Learned to Love Running, One Race at a Time
