The agency launched an investigation against the 54-year-old woman after receiving an anonymous tip and found that while she had been collecting sick pay, she was also one of the top runners in her competitive class in Sweden.
Over the past few years she had participated in a number of events around Sweden and was an active member of two sports clubs.
The woman started claiming benefits back in 2005 and continued until the agency caught up with her in 2014.
She stated in her original application that her back and stomach were troubling her, writing that she "felt like needles were poking the soles of her feet" and that her "legs and back were hurting and the ache spread to her lungs and sides".
Because of this pain the woman stated that she was unable to even vacuum her home or drive a car, and the pain was supposedly so bad she fainted and had to take heavy pain-killers.
Wednesday was deadline day for the 54-year-old to return the funds to the Social Insurance Agency (Försäkringskassan). She however continued to maintain the legitimacy of her claim, explaining that the reason for her running career was that she had been ordered to get as much exercise in as possible.