Are Elite Athletes At Higher Risk Of Heart Problems & Premature Death?

The untimely death of Rab Wardell, just days after becoming Scottish Cross Country champion, raised fresh concerns about the risks of extreme endurance training. Sadly, it is not unheard of for young athletes in prime physical condition to suffer cardiac arrest or even sudden cardiac death, where the heart suddenly stops. When this happens it's sure to catch the attention of the media and generate a lot of speculation.

The first thing to address is something several readers were questioning in the above article about Rab's death: does this have something to do with Covid vaccines? The short answer is no. Although vaccines have been linked to a slight increase in the risk of myocarditis or pericarditis (heart inflammation), the absolute risk is low - about 30 cases per million for the highest-risk age group, according to this study published in the British Medical Journal. There is no evidence that people are at increased risk of cardiac arrest after taking the vaccine. In fact, the study found that vaccination was linked with a lower risk of cardiac arrest or death. Unfortunately, contracting Covid-19 its self has been linked to a dramatic increase in the risk of various heart problems, including a 72% rise in the risk of heart failure. For more information on this, check out this article.

The other question readers were asking was whether repeatedly pushing the human body to the limit in pursuit of performance is dangerous. In other words...

Could too much exercise be bad for you?

There is plenty of published research into the effects of exercise, and without question, for most people doing more exercise reduces the risk of death and cardiovascular problems dramatically. In fact, exercise has been described as the best medicine in the world, as it reduces the risk of various diseases while improving mood, sleep, mental health, sexual function, bone density, and brain health, (among other benefits). If you only remember one thing from this article, it should be that exercise is good for you. However, it's not quite as simple as more exercise always equals a longer life.


This 2015 study published in the Journal of the American Medical Association (JAMA) pooled data from a whopping 661,137 people and compared how much exercise they performed outside of work to their all-cause risk of dying during the follow-up period, which was on average 14 years. Even after adjusting for lifestyle factors (age, gender, race, education, smoking status, cancer history, heart disease, alcohol consumption, marital status, and BMI), they found that people who did more exercise were less likely to die in that time than people who did little to no exercise, but the benefits diminished with higher "exercise doses". So far, so intuitive.


However, the highest exercise group (people doing more than the equivalent of 750 minutes (12.5 hours) of vigorous exercise per week - that's ten times the minimum amount recommended by the 2008 Physical Activity Guidelines for Americans - had a slightly higher risk of dying than those doing the optimum amount of exercise (around 3-10 times the recommended minimum). Specifically, the lowest risk groups had a 39% lower risk of death than those doing no leisure time exercise, but people doing more than ten times the recommended minimum had only a 31% lower risk.

It's important to underline that this highest-exercise group (on the far right of the graph) still had a substantially lower mortality risk than those getting less than the recommended amount (the two groups towards the left of the graph), which includes most people. And whether the reduction in risk of death is 31% or 39% compared to no exercise, if there was a pill that delivered that result everyone would be taking it.

But while this study adds even more weight to the message that exercise is good for you, it does suggest that those doing extremely high levels of exercise could start to increase their risk of dying as they add even more training to their routine. And while only 0.6% of those involved in the study fit into that highest-exercise group, elite athletes like Rab Wardell might be in the top 0.01% of the population in terms of exercise dose. So, are the elite of the elite at higher risk?

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What about the fittest cyclists in the world?

This 2013 study from Paris Descartes University looked into Tour de France cyclists. The researchers followed up on all French participants in the Tour de France who competed between 1947 and 2012. Of the 786 cyclists who participated at least once in that time, 208 (26%) had died by 1 September 2012. That works out to be a 41% lower risk of death than what would be expected in the general French male population.

Does this prove that competing in high-level sports is good for you? No.

To quote the authors' conclusion: "Our results do not allow us to assess in detail the balance between positive effects of high-level sports activity and selection of healthy elite athletes, vs. any potential deleterious effects of excessive physical exercise or alleged doping." In other words, it may be that cyclists talented enough to compete in the Tour were already naturally healthy, so it's unclear whether the combination of intense training, competing (and possible doping) shortened or lengthened their lives. However, this study does put to bed the idea that ultra-high-level athletes are at an increased risk of dying young than average.

So how do we reconcile this with the many news stories of endurance athletes dying during or shortly after a sporting event?

It's well known that elite athletes are more likely to have heart arrhythmia, an irregular heart rhythm which can occasionally lead to sudden cardiac arrest, where the heart stops pumping due to problems with the heart's electrical system. This is not the same as a heart attack, a blockage of the blood vessels supplying the heart, which is far less common among athletes than sedentary individuals. The risk of cardiac arrest may also be raised in the short term during especially strenuous activity - such as racing. However, this seems to be outweighed in the longer term by the benefits exercise brings.

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Short-term risk and long-term safety: insights from one of the largest and longest-running endurance races

One of the best sources of information on this comes from a huge and long-running cross-country skiing race in Sweden, called Vasaloppet. The 90 km race has been running for over ninety years and draws in huge numbers of competitors from elite athletes to, well, anyone capable of skiing 90 km, making it a treasure trove of data.

This 2015 study from Uppsala Universitet dug into the numbers. Over ninety years of racing and over half a million competitors, thirteen people died during the race. That works out to about 1 in 50,000 skiers. For comparison, in the USA you have a seven times higher risk of dying in a car accident over a given year.

Still, that's about 7.7 times the number of deaths you'd expect from the same number of people in the general population over the same amount of time just living normally. Twelve of those people died due to cardiac arrest - 22.1 times as many as would be expected in the general population. The increased risk of cardiac arrest per hour while ski-racing was similar to that during marathon running. All deaths occurred in men and most were among those between 51 and 70 years of age.

But that's not the end of the story. The study also compared the skiers' risk of cancer and cardiovascular disease to the general population in the years after competing in the event. Here's how the authors summarise the findings: "The short excess mortality in endurance physical activity is by far outweighed by the long-term protective effect of exercise in cardiovascular diseases and cancer."

This is backed up by an earlier study published in the Journal of Internal Medicine which followed up on people who raced the Vasaloppet between 1989 and 1998. Much like the Tour de France study mentioned earlier, they found that the ski racers had about half the overall risk of dying during the follow-up period than what would be expected in the general population after adjusting for age. This result was similar for all categories of skiers when ranked from fastest to slowest, but those who raced multiple times were at an even lower risk than those who competed once.

In other words, there is a short-term increased risk of dying due to cardiac arrest while competing in this endurance race, but in the longer term, people who compete are less likely to die prematurely than you'd expect from the general population. Like with the TDF study, this doesn't prove that racing the Vasaloppet extended their lives, as those who chose to compete were likely already healthier in general than the average person, but it does show once more that athletes are much less likely to die young than average, despite the increased risk during the event. So while there are real risks associated with high-level exercise, not exercising enough is a far bigger risk in the long run.

Averages disguise a spread

Heart disease is sadly very common. It's the biggest killer in developed countries, killing one in six Americans, and too little exercise is a major cause. So there's no contradiction in saying that athletes face a lower risk than average, but the risk of heart problems is still significant. The fact that athletes face less risk than sedentary individuals is perhaps like the fact that air travel is safer than driving; it doesn't mean the risk is negligible or that it can't be reduced further. Also, the studies we've looked at so far can only tell us about the average risk faced by athletes, and the risk is not evenly distributed.

This study called Sudden Cardiac Death in Athletes compares risk factors for SCD in National Collegiate Athletic Association (NCAA) athletes. The table below shows how sex, race and sport affect the odds dramatically. For comparison, the risk of SCD among older athletes aged 35-65 in another study was slightly higher, at about 1 in 46,000 per athlete per year, and this article in the British Medical Journal puts it at between 1 in 50,000 and 1 in 80,000 for athletes in general. To try and give those numbers some context, the average risk of dying in a traffic accident in the USA in 2004 was 1 in 6,197.


The most important risk factor is called Hypertrophic Cardiomyopathy (HCM). It's a genetic condition that affects about 1 in 500 people. It causes the heart muscle to become thick and rough which can impair heart function or predispose people to arrhythmia. Most people with HCM have a normal life, usually without any symptoms, and the absolute risk of sudden death is low, but it's the most common cause of sudden cardiac death in young people and athletes. For this reason, people who are diagnosed with HCM are often advised to avoid competitive sports and high-intensity exercise, but screening is rare so many HCM cases go undiagnosed.

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Should you consult your doctor? What about screening?

I spoke with an NHS GP to fact-check this article and to ask when people should approach their doctor:

“I would encourage people experiencing palpitations, chest pain, shortness of breath, or lightheadedness to come forward and discuss this with their doctor. Of course, there are lots of different causes of these symptoms and investigation/management will be decided on a case-by-case basis agreed between the patient and their clinician”.

“In particular, people experiencing exercise-induced syncope (fainting/loss of consciousness), exercise-induced seizures, or those with a family history of sudden death should discuss this with their Doctor since this would most likely require further investigation/management”.

"Screening athletes prior to competition for unrecognised heart conditions has been proposed. However, there is much disagreement regarding the benefits vs harms of such screening programmes amongst experts and international recommendations vary. (Harms resulting from false-positive screening results, leading to athletes’ disqualification from competitive sports, psychological and financial harm and the resulting medical follow-up with unknown benefit). With current evidence, [more information on that here or here] there is no such screening programme in the UK."

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Interview with Lennard Zinn, co-author of The Haywire Heart.


Yes, that’s exactly right—it’s outweighed by the overall benefits of exercise and the selection of healthy participants. Those studies look at mortality and don’t drill down into actual causes. And on the subject of overall mortality, I suspect that the chances of finding any significant numbers of smokers among them is vanishingly small, thus cutting mortality significantly right there. Same goes for obesity, another big risk factor for mortality. I also suspect that they are statistically less likely to drink and drive than the average population, although that is going further out on the limb of conjecture, and I suppose that is less of an issue in Scandinavia, and perhaps in France, than it is in the USA.

Do you think there should be more emphasis on the risk of reduced quality of life as a result of heart problems caused by overtraining, as opposed to the risk of premature death?

Yes. The caveat is that saying that requires a value judgment to say that being able to ride or run up a long hill faster than athletes 20 years one’s junior or to compete in dozens of races/year is a higher quality of life than walking for an hour a day. I personally had to give up a lot after developing an arrhythmia—namely hard training, racing, the camaraderie found in those things, the satisfaction of outriding other people, and the competitive reaction in general. On the other hand, I enjoy my life immensely, and, now that I have become accustomed to it and could care less if other people pass me on a bike or on foot, I would not want to go back to that lifestyle I had. I do miss the travel, the friendships, and the burn feeling; I don’t miss the compulsion.

What would the stereotypical patient/athlete most at risk of these heart problems look like? It seems to mostly affect male athletes, some studies suggest taller athletes are at greater risk, perhaps someone overtraining into their fifties. And what about caffeine - is that a problem?

I think the link to caffeine is under question. The rest of those, yes. I think taking into account work and family commitments in that list is overlooked, too. People in this category tend to be successful, which is why they have the time and resources to train and race so much, which means they probably also work a lot, and combining lots of work with lots of racing and training tends to also accompany being stretched thin when it comes to family, too.

I think the overtraining, and under-resting is particularly an issue for people who were already competing at endurance sports in their 20s and 30s—I know of very few in this group who recognize(d) how much less they could (safely) train and how much more they should rest once in their 50s. I think it is endemic in this group to want to do close to what they used to do in their prime. Certainly, that was the case with me.

What do you think can/should be done to reduce the risk?

Take a deep breath and remember why you started doing the sport in the first place—which in most cases would be for fun. Then notice whether what you are doing is bringing you joy or not. And realize nobody other than the people you race with care one iota about what your placings are in masters races.

Recognize that just taking a walk with your spouse or your dog can bring great satisfaction for yourself as well as for them and is not necessarily a downgrade from pushing yourself as hard as you can up a big climb or through an interval session.

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Key Points

• Excercise is good for you! Multiple studies show a variety of benefits to exercise, including a longer life.

• One study suggests there could be an optimum amount of exercise for longevity. On average. those training extremely hard (more than 12.5 hours of vigorous exercise equivalent per week) had a slightly higher mortality risk than those training slightly less (4-12.5 hours of vigorous exercise per week), but still had a lower risk than those doing too little exercise.

• French Tour De France competitors were significantly less likely to die young than their counterparts in the general population.

• Large studies into endurance cross-country ski racers show a short-term increased risk of cardiac arrest and sudden cardiac death during the event, but this is far outweighed in the longer term when it comes to the overall risk of premature death.

• Athletes are more likely to develop an irregular heart rhythm (arrhythmia) and other heart abnormalities, but this too seems to be outweighed in terms of overall risk.

• Although the average risk of cardiac death in athletes is low (between 1 in 50,000 and 1 in 80,000 per year), evidence suggests the risk is higher for those who are male, tall or black, and the most important risk factor is a genetic condition called Hypertrophic Cardiomyopathy (HCM). HCM is the commonest underlying cause of sudden cardiac death.

• Anyone with a family history of cardiac arrest, or those experiencing palpitations, lightheadedness, faints, chest pain, shortness of breath, or passing out during exercise should consult their doctor. They might suggest checking for HCM and those diagnosed with the condition are often advised to avoid intense exercise.

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