Feel free to let your comments below…
Many news agencies are reporting on a research study presented at the American College of Cardiology annual meeting that suggested that triathletes have a significantly higher risk of heart attacks (myocardial infarctions) while participating in a triathlon. Having had a chance to read a copy of the presented study, the news accounts are a little misleading. The actual study looked at the incidence of sudden death in triathletes, not “heart attacks” as is being widely reported.
The study looked at reported deaths at USA Triathlon-sanctioned races over a two year period (2006 and 2007). Out of 922,810 triathletes in 2,846 triathlons there were a total of 14 deaths – roughly an incidence of 15 in 1 million participant. According to the study, 13 of these deaths occurred during the swim while the fourteenth fatality occurred due to a bike accident. Out of the 14 deaths, autopsies were performed on only 6 of the triathletes, and from that group of 6, four of the triathletes were found to have underlying heart disease. The other two autopsies reported normal hearts with no evidence of heart damage.
The lead study author commented that the cause of the fatal cardiac events may be due to coronary artery vasospasm, potentially a combination of the high intensity effort during the swim and cold water temperatures. However, its not evident if the water temperatures of the events were the fatalities occured were compared to the water temperatures at triathlons where there were no fatalities, or if the deceased triathlete’s open water or cold water swimming experience was also compared to the rest of the triathletes participating in the races during that same time.
I think that the reality is that some of the deaths are due to the “cold shock” response which is more of a respiratory problem – that gasp that you get when you jump into cold water and has been well-studied in dive medicine. For some people, they have a more severe breathing response to cold water and start gasping and lose control of their normal breathing. In the chaos of a mass triathlon start, that could result in aspiration of water and drowning without any significant cardiac involvement. Additionally, a recent study out of Penn State suggests that coronary blood flow is actually increased during cold water exposure, which would contradict the coronary vasospasm/constriction hypothesis of the triathlon heart attack researchers.
If you want to find out more about the effects of cold shock, the US Coast Guard has a great YouTube video
How does the number of triathlete fatalities compare to other sporting events? The incidence of fatal events at marathons has been estimated to be between 4 to 8 marathon runners per 1 million race participants.
Another study in the medical journal Circulation looked at the impact of training volume of marathon runners on heart function and found that runners with lower weekly running volume (less than 35 miles/wk) had a higher incidence of elevated proteins in the blood that may indicate heart muscle damage compared to marathon finishers that trained more than 45 miles/week leading up to the race.
What does the American Heart Association have to say about the risk of heart attacks during exercise? Check out the American Heart Association Scientific Statement on Exercise and Acute Cardiovascular Events.
If you’re still looking for more information, check out this editorial in the European Heart Journal that looks more in depth at possible reasons for some of the increased cardiac events seen in marathon runners.
The Peak Performance web site also has a good review about the risk of dying from a heart attack during exercise.
What’s my take?
Any death is tragic.
The fact that someone dies during an event that promotes exercise and a healthy lifestyle (well, if reading Slowtwitch.com all day at work and worrying about the aerodynamics of the latest tri-bike to be released is considered “healthy”) doesn’t make it any less (or more) tragic.
However, the reality is that these individuals that did have cardiac events during the triathlon probably had significant cardiac disease despite their triathlon lifestyle – similar to Jim Fixx’s too early death, the author of the Complete Book of Running that many credited with kicking off the running and health revolution during the 1970′s.
While they may have shuffled off this mortal coil before their time, hopefully they enjoyed the experience beyond what they would have if they had never found triathlons.
-Doc John
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Thank you very much for this info. I read the orginial article and became quite concerned. I an a 51 year old newer triathlete and have symptoms of shortness of breath, chest pain, etc. which lasts.Wondering if I should get acurrent physical which is more extensive. Do you think I should? What tests should I ask for? I don’t have these issues while in the pool.
Thank you. Sara
Sara,
I’d highly recommend that you talk to your primary care physician about your symptoms. While they may be nothing more than anxiety from the swim start, it would be prudent for the physician to discuss what other cardiac risk factors that you may have which would guide their workup.
-Doc John
The studies we have regarding sudden death in triathlon and other sports suggest that the cause of lethal arrhythmias are preexisting cardiac disease in only a minority of cases.
Since there have been few risk factors identified (including level of fitness) I would suggest earlier intervention with defibrillators should be considered.
This would require more rapid identification of the victim, and defibrillation in a boat rather than on the shore. Too late on shore.
We might save some lives.
Thanks Dr. Martinez for responding to this article. My first triathon was a DNF because I hyperventilated during the early portion of the swim, due to cold water and anxiety. It’s subsequently been my practice to spend at least 8-10 minutes in the water before a race, especially in water less than 60 degrees to acclimate. I also spend a few minutes either on the bike or on a short run to get my heart-rate up a little prior to a race. 7:00 race starts can be tough without a little warmup.
Thanks, Rob
Eric,
Thanks for the comment!
I don’t think anyone would disagree with early intervention – and there should be a well-thought out emergency medical plan for events such as a potential cardiac and/or drowning victim in the water.
I would also submit that we (the triathlon community as well as physicians) also probably need to do a much better job with prevention of sudden death by identifying possible risk factors before it becomes an issue. Just because someone is “fit” enough to pull on a wetsuit for the swim start doesn’t mean that they are “healthy” enough to do so.
Thanks for this article John. Much more comprehensive than the Yahoo article about how dangerous triathlons are circulating around the internet. I’m twittering this and sharing it on Facebook.
Poor swimming technique, lack of water experience, and swimming in a new tight wetsuit, can also attribute to water aspiration and an in-water panic. Whether this is related or not, make sure to take the time to experience praciting swimming in your wetsuit, and in cold, open water BEFORE the race. If your skill level is low, please seek help from a qualified instructor. There is no way for race directors to screen racers and identify possible risk factors so take responsability for your own safety. Obviously accidents can and will always happen which is why safety personnel are in place however, the prevention starts with YOU.
Happy Swimming!
Coach Ruthy
Good discussion. In my humble opinion, It’s difficult (but not impossible) to “train” for the absolute excitement that’s churned up when so many eager people head out into the water at once — some very competitive, others kind of new and scared. It’s a rush that’s wonderful and frightening at the same time because so much is going through your own mind related to the race. Some love it; others gasp. Newcomers can/should train and acclimate to the water temp., waves and other conditions, but there is a lot of churning, some Help-me! calls for assistance and other distractions that kind of stretch the ol’ effort/concentration/ reaction modes. And in water, for some, that can lead to panic. Just be ready, Talk to others, be confident, and just cruise, catch your breath when you have to. Have fun!
Great article! I couldn’t agree more. As a triathlete and scientist that studies heart disease, I think exercise-related deaths are definitely due to individuals with pre-existing conditions. Furthermore, with the guidance of a doctor before starting a new exercise program, most people will enjoy increased cardiovascular health that comes with regular exercise.
If it was easy and there was no risk involved, what fun would it be? Wonder what the risk for me would have been if I didn’t lose 100lbs and become a triathlete???? Think my odds would have been better than 15 to one million?
I’ll take my chances in the water (bike and run) and would recommend anyone else who wants to tackle triathlon do the same.
Train hard, train smart, and the reward awaits you…
“The person who risks nothing, does nothing, has nothing, is nothing, and becomes nothing. He may avoid suffering and sorrow, but he simply cannot learn and feel and change and grow and love and live.”
-Leo F. Buscaglia
Mild Hypothermia, is clinically defined as body core temperatures between 96.8°F(36°C) to 91.4°F(33.3°C). I became hypothermic last summer after starting a 1/2 IM in a Colorado resevoir in early September. It cost me a race I had hoped to win. I am a seasoned triathlete and wore a full wetsuit in what was probably water in the mid-low 50′s. I actually felt fine in the water except at the end of the swim when my feet started going numb. I couldn’t function in the transition area and actually attempted to RIDE my bike out of T1(Duh). Thankfully a friend on the sidelines pulled me out after seeing my dysfunction and odd behavior. No one from the race crew seemed to really care, and I was not the only person in this situation.
On the way to my car to rewarm, we passed the paramedics, asleep in their vehicle with the engine running and the heat on
The original article was the worst reporting I have seen in years. First, no mention is made of the positive health benefits the million participants received. How many would have had coronary episodes if they didn’t exercise? More than 13 I believe. Cold water response ? None of the evnues I saw were really below 60 degrees. Besides, most of the deaths occurred in the last few hundred yards – NYC, HyVee and the Oregon race were all near the finish. There is a Japanese study showing the constriction of the wet suit probably has more to do with the arrythmias than anything else. Lets try to look at the glass not half empty but just twice as big as it needs to be