Olympic runner Jenny Simpson has announced her retirement from the sport, citing medical advice following a cardiac arrest incident earlier this year. The decision comes just over two months after she collapsed during a race in North Carolina.

Simpson, 39, revealed her diagnosis and decision in an Instagram post on Thursday. She stated that while she is recovering, her medical condition makes it dangerous for her to continue running competitively. "My future is an incredible gift. It’s hopeful, and it will continue to have great purpose. But my diagnosis also means it would be dangerous for me to return to running. That chapter has ended. Thankfully, my story hasn’t," Simpson wrote.

The three-time Olympian, who won bronze in the 1500-meter event at the 2016 Rio Olympics, experienced a second cardiac arrest after being initially revived with CPR and an AED at the Sir Walter Running Pop-Up Mile on June 17. She was subsequently placed on life support and transferred to Duke Hospital for advanced care.

Simpson was diagnosed with arrhythmogenic right ventricular cardiomyopathy, a condition that can cause irregular heartbeats and sudden cardiac death in individuals who appear healthy, according to Johns Hopkins Medicine. "My body was dying, but my spirit wouldn’t give up. I fought for my life," she stated.

Simpson expressed profound gratitude for her career, which included competing in events from the mile to the marathon globally. Before turning professional in 2010, she set six NCAA records and won four national championships while competing for the University of Colorado.

"My relationship with running must change. My love for it is stronger than ever," Simpson said. "I won’t be out there running beside you, but I’ll still be right where I belong — supporting and cheering for this running community that has given me so much."