Deaths during running: Is exercise safe?

Sudden death during exercise:  The media, risk and running

For those who have not heard or read the news, three runners died during the Detroit Marathon/Half-marathon last weekend.  All three were running the half-marathon, and were aged 26, 36 and 65.  The three collapsed within 16 minutes of each other during the race.  The timing, the wide spread of ages, and the fact that three deaths occurred in one race (which was not hot, I might add) have given the story 'legs', and it was even covered on CNN.

Whenever this kind of incident happens, there is debate and discussion around the safety of running.   It's always bad press for running.  It is a topic that pops up fairly regularly, and we've actually covered it in a fair amount of detail here on The Science of Sport.  I'm not going to go into enormous detail on sudden deaths during exercise again, but for those who are interested, you may like to read the following posts:

• Sudden cardiac death in runners (a post in response to Ryan Shay's death)
• Sudden death during exercise - practical implications and perspective
  

A general perception of safety

So as I said, I wouldn't ordinarily post on this topic again and in the case of the Detroit runners, I don't know the cause or any details, and so it would be wildly speculative to discuss specifics.  However, this latest incident, and the media reporting around it, reminded me of a thought I'd had while watching the NBC coverage of the Chicago Marathon about 2 weeks ago.

You may recall that Jonathan and I were in the control area, doing real-time pacing for the race, and also spent some time in the medical tent.  But it was watching NBC's coverage, that I was struck by the fact that the person who was interviewed the most during a 3 hour broadcast was the race doctor, George Chiampas.  On no fewer than four occasions, Dr Chiampas was featured in a two -minute interview, giving his thoughts on race hydration, race safety, post-race safety, recovery, training and so forth.  And while he answered the questions very well, it was clear that the 'safety/danger' of running was of utmost importance to the broadcaster.

It struck me that there is a very real perception among mainstream media in the USA (remembering I'm from South Africa and so normally unaware of this message) that running is a risk.  That is, viewers who watched the broadcast of Chicago and who were NOT runners would be left under no illusions that attempting to run a marathon is a dangerous task.  The "shock and fear" coverage, which implies danger at every turn, sends a clear message that if you run a marathon, you are taking a chance with your life.

And this unfortunate, because it ignores the whole other side of the argument, and does so with little to back it up other than infrequent and over-hyped incidents.  A thoughtful, balanced approach would cover two additional aspects:

1. It would consider whether the risk of death during running is in fact greater than during any other activities, and;
2. It would look at whether the average  runner (from recreational to the marathon) was deriving a benefit from running, and whether this person was in fact less likely to die than someone who chose to stay on the couch because of all these "life-threatening" risks.

Millions of hours invested, but even stats don't tell the full story

Then there is the statistical approach, which many resort to in cases like this.  I read in a report from Fox News that a total of 425,000 runners completed marathons in the USA in 2008, and another 715,000 completed half-marathons.

If you convert that to time, assuming that the average marathon and half-marathon time is 4 hours and 2 hours, respectively, then you can work out that a total of 3.1 million hours of running time goes into those races.  And this does not include the training, or the 5km and 10km races done along the way.  If you assume that the average person trains 2.5 hours a week for 3 months to run a marathon or half-marathon race, then you get a grand total of 34.2 million hours of training time per year for those runners.  The total running time for marathon and half-marathon runners in the USA per year?  37.2 million hours of running (and this is an underestimate, I must point out - it does not take into account the millions who spend an hour a week jogging in the gyms, or those who train but don't race)

So what is the frequency of mortality for these runners?  Fox News reports that about 6 deaths per year occur during races.  How many during training?  We don't know, unfortunately.  But the point I'm trying to make is that these deaths are rather less common than they may seem - one per million hours, perhaps?  One per three million hours?  Until that is quantified, reports that marathon running is dangerous are simply irresponsible, the result of a classic 'media-led knee-jerk reaction', where news reporting makes us over-estimate the prevalence of such events.  A classic example is shark attacks - they are exceedingly rare, but when they happen, they're so dramatic that they receive hyped-up media exposure and so we think they're more common than they are.  I suspect the same is true for running-related deaths.  (What would be great is to compare this number with other activities - driving your car, flying, playing other sports.  If there are any economists or actuaries out there who know this, please speak up!)

The real story - the benefit that the media don't report

But these stats don't tell the whole story anyway.  What you really need to ask is whether exercise adds up to a longer, healthier life, even taking into account what I believe is a tiny risk.  In other words, you need to look at the overall benefit of being active, and ask whether those who run are less likely to die than those who do not?  There is no doubt, based on the evidence, that exercise reduces the risk of morbidity (disease) and mortality (death).  One of the most famous names in exercise science and health is Ralph Paffenbarger, and he demonstrated pretty clearly that increasing exercise was associated with decreased risk of disease and death.  The most famous study is perhaps this one, his Harvard Alumni paper.

Paffenbarger went so far as to show that people who exercised AND smoked, were less at risk than those who didn't smoke, but didn't exercise either.  So, if you want a debate about the benefits of exercise (and I include running here), the real issue is whether those three deaths, and then dozen or so that seem to happen each year during running, outweigh the fact that those same people, if inactive, would have a lower life expectancy and health status?  I doubt it does.

And I wish that the NBC, and all the other media covering running events here in the US and the rest of the world, would acknowledge that instead of focusing on the small risk of injury or death, there is a far bigger positive outcome to being active.  Maybe in future, doctors like George Chiampas will be explaining why those sitting on their couches SHOULD be getting up to run, rather than telling those who are running how not to hurt themselves doing it!

Fitness does not protect you, but nor does being under-trained increase your risk

One final point I have to make, in response to what I've seen is being discussed about this issue, is that people are not necessarily more likely to die from a cardiac event during exercise if they are untrained.  A lot of people have said that people who die during marathons are themselves responsible, because they're running when they are not fit enough.  This is not true, to the best of my knowledge.

The reality is that people who die during exercise have some underlying, probably undetected condition that predisposes them to a cardiac event during exercise.  Those who are simply unfit don't die - they just stop at the 10 mile mark (or sooner) and walk the rest of the way, because their brain does not allow them to continue running.  The fact of the matter is that there are conditions that predispose us to sudden cardiac death, and exercise can bring this out - but it could happen to the elite (Ryan Shay, a few soccer players in recent years) or to the average runner.  It's not that they're unfit or undertrained.

Of course, behaviours contribute to some deaths - overdrinking, for example, can lead to hyponatremia and death.  But even here, the criticism belongs with those who advocate excessive drinking, the dangers of "dehydration" and advertise sports drinks to unknowing consumers, not to the athlete who makes the mistake.

So in the light of the latest events, and until toxicology reports are in, deciding on the cause is premature.  Agreeing that it's sad for all involved, but recognizing that it's not running that killed them, is the way to go!

Ross