How Safe Is Long-Distance Running for Your Heart?

Introduction

Running marathons and half-marathons has become more popular than ever. Between 2010 and 2023, over 29 million people finished these races in the U.S. But with more runners on the road, concerns about health risks—especially heart-related ones—have also grown. A recent study helps us understand how often cardiac arrests happen during races, who is most at risk, and how outcomes have changed over time.

Heart Risk in Races Is Rare but Real

The good news is that cardiac arrest during long-distance races remains rare. On average, just 1 out of every 166,667 runners experienced cardiac arrest. Even better, the number of people who die from these events has gone down significantly since the early 2000s.

This improvement is largely thanks to better emergency planning. Races now have more trained staff, defibrillators placed along the route, and runners who know CPR. As a result, survival rates have doubled—from 29% to 66% since 2000.

Men and Marathon Runners Face Higher Risk

While running is safe for most people, some groups face a higher risk. Cardiac arrest is more likely to happen during marathons than half-marathons. Men are also more affected than women. This is especially true for older male runners doing the full marathon distance.

Interestingly, most cardiac arrests happen toward the end of races. This is likely when runners push themselves harder to finish strong, increasing the strain on their hearts.

The Main Cause Is Often Heart Disease

The study found that the most common cause of cardiac arrest in races is coronary artery disease—a condition where the blood vessels that supply the heart are narrowed or blocked. This was more common than other known causes like hypertrophic cardiomyopathy, a condition once thought to be the main risk in athletes.

In some cases, the cause remains unknown even after thorough tests or autopsies. However, sudden arrhythmic death—a kind of unexplained heart rhythm issue—was often suspected in these cases.

How Races Have Become Safer

One of the biggest reasons for improved survival is quick action. Every cardiac arrest survivor in the study received bystander CPR, and most had fast access to a defibrillator. These actions can double or even triple the chances of survival.

Race organizers have also done more to prepare. They now train volunteers, place emergency teams throughout the course, and make sure medical services are nearby. These steps have made races safer for everyone.

Final Thoughts

Running marathons and half-marathons remains a healthy and rewarding activity for millions of people. Although cardiac arrest during races is rare, it’s important to be aware of the risks, especially for older runners or those with heart conditions.

Simple steps like regular heart checkups, knowing your limits, and learning CPR can go a long way. Thanks to better safety planning, long-distance running is not only more popular—but also safer—than ever before.