Jenny Simpson Reveals Rare Heart Condition After Cardiac Arrest, Rules Out Return to Running.

Three-time Olympian Jenny Simpson has confirmed that she will not return to competitive running after surviving a sudden cardiac arrest that nearly claimed her life earlier this year.

The 39-year-old American revealed on Thursday that doctors diagnosed her with arrhythmogenic right ventricular cardiomyopathy (ARVC), a rare inherited heart condition that can cause dangerous heart rhythms and sudden cardiac arrest. Simpson said the diagnosis means running is no longer considered safe for her.

The revelation follows a medical emergency on June 16, when Simpson collapsed while pacing a mile group at the Sir Walter Running Pop-Up Mile in Raleigh, North Carolina. Responders found that she had suffered cardiac arrest and used CPR and an automated external defibrillator to restore her pulse before she was taken to hospital.

Her condition remained critical after the initial rescue. According to Simpson's account, her heart stopped again in hospital and she was placed on life support before being transferred to Duke University Hospital for advanced treatment. She eventually recovered sufficiently to leave hospital and has continued her recovery at home in Colorado.

Simpson's diagnosis brings a definitive end to the competitive chapter of a career that had already made her one of America's most accomplished middle-distance runners.

She represented the United States at three consecutive Olympic Games, Beijing 2008, London 2012 and Rio 2016, and won bronze in the 1,500 metres at Rio. Five years earlier, she became world champion in the same event at the 2011 World Championships, later adding silver medals at the 2013 and 2017 championships.

Simpson had formally retired from professional competition in 2024 after running the New York City Marathon. Her latest announcement is therefore less a conventional retirement from professional athletics than a confirmation that the sport she continued to participate in recreationally and through her work can no longer safely be part of her life as an athlete.

The circumstances have also changed the way Simpson views what comes next. Rather than presenting the diagnosis simply as the loss of a career, she has spoken about surviving an event that could easily have had a different outcome and about being grateful for the opportunity to move forward.

That outlook is particularly significant given how closely running has been tied to Simpson's identity. She remains involved in the sport as chief running officer at Fleet Feet, meaning her relationship with running is unlikely to disappear even though she can no longer compete.

Her story also underlines the unpredictable nature of cardiac emergencies in sport. Simpson was participating in a community running event rather than a major championship when she collapsed, and the immediate response from people at the scene, followed by emergency medical treatment, proved critical to her survival.

For a runner whose career was built around pushing physical limits, the next challenge is now fundamentally different: accepting a future in which competition is no longer an option while remaining connected to the sport that shaped much of her life. Simpson's decision is not simply the closing of a decorated athletics career; it is the story of an elite athlete forced to redefine what comes after the finish line, and of a survivor choosing to look ahead rather than back.