When you’re gearing up for a marathon, you’re probably excited to test your physical and mental limits, connect with fellow runners and experience that incredible sense of accomplishment at the finish line. Alongside questions about pacing and fueling strategies, recent research from Keio University in Japan looks at another concern: could your heart be at risk?
The study: who is at risk?
The study, published in the medical journal Resuscitation, analyzed data from 516 marathons held in Japan between 2011 and 2018, involving over 4.1 million participants. The researchers identified 69 cases of cardiac arrest, translating to an incidence rate of 1.7 per 100,000 runners. The majority of cases (96 per cent) involved men, with the risk climbing significantly with age. For men aged 60 and older, the rate was 5.5 per 100,000—six times higher than for runners under 50.
Despite these findings, the overall likelihood of cardiac arrest remains low. “The survey does not imply that elderly men should completely stop participating in marathons,” explains Tomohiro Manabe, a cardiovascular expert and lead researcher. Instead, he stressed the importance of health checkups, particularly for older runners, as these can help identify underlying conditions like coronary artery disease that increase risk.
New study finds exercise improves heart health even more for those with anxiety and depression
A look at the numbers
The median age of runners who experienced cardiac arrest was 53, and the risk increased with each decade of life, with men in their 40s impacted at a rate of 0.9 per 100,000; those in their 50s at a rate of 2.6 per 100,000 and men 60 and older at a rate of 5.5 per 100,000.
Women faced significantly lower risks, with an incidence rate of just 0.3 per 100,000 participants. Among the three women affected, all were under 50, and no age-related trend was observed.
What can runners do?
Preparation is key. Some medical professionals recommend marathon participants go over a health checklist before race-day especially men over 60. Regular medical exams can identify conditions like angina or coronary artery disease, which are linked to cardiac arrest and are more common with age. Manabe emphasized that the study is not a call for older athletes to quit marathons entirely. “The risk for individuals from this age group can more easily be assessed via prior health checkups,” he noted.
Emergency measures save lives
The research team also emphasized the importance of first-aid systems at race events. The use of automated external defibrillators (AEDs), and administering immediate CPR can be life-saving. Moving forward, researchers plan to study how weather conditions impact risk and assess the effectiveness of existing first-aid protocols.
The takeaway
The overall likelihood of cardiac arrest during a marathon remains very low, and runners should remember that the heart health benefits of exercise far outweigh any risks. It’s always worth checking in with your physician before you begin a new exercise regime, and remembering that risk rises with age, particularly for men over 60. Taking proactive steps—such as undergoing regular checkups and being aware of heart health—can help ensure that your biggest concern on race-day is how many sticky gels you can consume.
