Is Running Really Dangerous?

By Scott Douglas

Causes of Sudden Death
Signs and Symptoms
Precautionary Practices


The death of Ryan Shay during the U.S. Olympic Marathon Trials in November 2007 has unsettled many long-time athletes. After all, here was a 28-year-old 2:14 marathoner, with no history of relevant complaints, who suddenly collapsed and died in the sixth mile of a marathon while running well below his maximum. If it can happen to Shay, runners and other endurance athletes wonder, is anyone immune? Am I next?

Before we examine who is most at risk of sudden death while exercising, and what precautions to take if you’re susceptible, there are two highly important matters to consider. First, says Deepu Nair, M.D., chief of cardiology at the Cleveland Clinic in Cleveland, Ohio, “these are very rare episodes. The rate of sudden death in athletes is something like 1 in 50,000 people to 1 in 200,000 people, depending on which study you read.”

Second, says Jeffrey Rosenblatt, M.D., the chief of cardiology at Mercy Hospital in Portland, Maine, “the way to approach this issue conceptually is to look at people in general, not just athletes. For the most part, are there increased risks of being an athlete versus being sedentary? No! By being an athlete, you’re doing many good things for your health.”

With those caveats in mind, let’s start by looking at the most common causes of sudden death in athletes.

Causes of Sudden Death

Experts on athletic sudden death say that the cause depends on your age. “Over the age of 35, sudden death in athletes is generally caused by the same things that trigger cardiac events in general,” says Nair, a veteran of four marathons. Rosenblatt, a lifelong runner who has also done half-Ironman triathlons, agrees. “The most likely reason is coronary artery disease,” he says, “especially if you’re a man, just like it is for everyone of that age group, because it’s so rampant in our culture. Probably 50 percent of the population have plaque in their heart arteries by that age.” This scenario, for example, applies to former elite marathoner Alberto Salazar, age 48, who had a near-fatal heart attack in June, and former national-class marathoners such as Andy Palmer and Ed Sheehan, both of whom died on a run despite being highly fit masters runners.

“Under the age of 35, things are different,” says Nair. “Then it’s usually caused by a structural problem with the heart.” The leading causes among endurance athletes for this age group are:

  • Hypertrophic cardiomyopathy. This is abnormal thickening of the heart muscle. Because of the excessive thickness, problems can occur as blood leaves the heart.
  • Coronary anomalies. This is being born with heart arteries that don’t take the normal course to the heart. As a result, the heart can act as if arteries are blocked, and heart rhythm problems can develop.
  • Congenital aortic stenosis. This is being born with two rather than three heart valve leaflets. In some people with this condition, the leaflets can’t open well and the heart can’t force blood out, especially when the person is dehydrated.

Signs and Symptoms

“In 50 percent of sudden death incidents, there are no prior symptoms,” says Rosenblatt. “The first symptom is that you’re dead.” Still, there often are warning signs. For example, although Shay’s autopsy remains inconclusive at this point, he had known since his early teen years that he had a congenitally enlarged heart. According to Rosenblatt and Nair, the following signs can merit medical investigation:

  • Loss of consciousness while exercising. Similarly, feeling lightheaded or woozy, even up to an hour after working out. “Get this checked out even if it happens only once or twice,” says Rosenblatt.
  • A change in your functional status while training. That is, in the absence of a cold, flu or other obvious explanation, if you have increased heart rate, shortness of breath or a sense of decreased baseline fitness.
  • Heart murmurs. Extra or unusual sounds while your heart beats can be evidence of problems with the heart. Especially in younger people, they can indicate a structural problem.
  • A family history of inexplicable sudden death. This includes nonathletic sudden deaths, such as a close relative dying in his sleep at an early age.
  • Chest pain with exercise that’s distinct from to-be-expected exertional sensations.
  • If you’ve been told you have an enlarged heart. In this case, it’s important to distinguish between a congenitally enlarged heart and the enlarged heart many endurance athletes develop. Says Rosenblatt, “Experts can detect the differences between the two. Also, an athlete’s enlarged heart is reversible—if you stop exercising, within a few weeks you’ll see the thickness of the heart return to a normal state. That’s not the case with a pathological hypertrophic cardiomyopathy, where the genes have been altered indefinitely.”

If you have one or more of these symptoms, “my recommendation is to be seen by somebody with a sensitivity to sport,” says Rosenblatt, an adjunct professor of sportsmedicine at University of Southern Maine. “Be your own advocate. Say, ‘I’m an athlete and have this characteristic and want to get evaluated for it.’”

What form should that evaluation take? “Most people would do an electrocardiogram, but that’s woefully inadequate for these situations,” says Rosenblatt. “Much better would be an echocardiogram. You’ll do a treadmill stress test with ultrasound to provide a true imaging of the heart at work.”

In some cases, a knowledgeable cardiologist or internist will recommend that you wear a monitor for anywhere from 24 hours to one month to look for irregular heartbeats.

Precautionary Practices

If testing determines that you have a condition that predisposes you to sudden death, the next step is to determine how, if at all, to alter your exercise routine. Experts’ recommendations vary depending on your disorder.

If you have hypertrophic cardiomyopathy, “the most recent guidelines recommend exclusion from competitive sports, even in recreational activities,” says Rosenblatt.

Is low-intensity exercise safe in this case? “This is a very controversial area,” says Rosenblatt. “Sometimes doctors get caught up in being scared to death of getting sued, and fail to take into account a person’s quality of life. Our role is to inform and educate you about the risks and do our best to guide you, but ultimately, we should let adults decide how they want to live their lives. If you come to me with hypertrophic cardiomyopathy and say you want to run the Maine Marathon, I would advise you not to. But something like 30 minutes of light jogging and light lifting, if that’s important to you, then that’s probably okay.”

If you have coronary anomalies, “the recommendation is that you be excluded from all competitive sports,” says Rosenblatt. “If it’s really important to you to be a competitive athlete, you can have this condition fixed, just like you might have Achilles surgery. The arteries will be reimplanted in a safe way, and then you can resume competitive sports.”

Finally, if you have congenital aortic stenosis, “again, there are grey areas,” says Rosenblatt. In mild cases, current recommendations allow participating in all competitive sports, while in severe cases, you should refrain from competing. “This, too, can be fixed with surgery, if competing is important enough to you,” says Rosenblatt. “In all of these cases,” he says, “the best approach is to find someone knowledgeable about these conditions who will take into your quality of life.”

The bottom line, says Nair, is that “almost all runners are doing something good for their health. No one should stop running simply because of Ryan Shay’s death without consulting an expert in these matters.”