DIVING IN: Despite being the first leg and covering the shortest distance in any triathlon, swimming has proved to be the most deadly.
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Sunday's Nautica New York City Triathlon resulted in two deaths, both from cardiac events that arose during the event's initial swimming leg. A 64-year-old man and a 40-year-old woman were pulled from the Hudson River before they could complete the 1.5-kilometer swim from a wharf near Manhattan's 96th Street down to the West 79th Street Boat Basin. Both athletes were taken to a nearby hospital in cardiac arrest. Police said 26 others were removed from the water needing assistance for minor injuries or pains that arose during the swim portion of the competition.
The man, identified as Michael Kudryk of Freehold, N.J., was competing as part of a three-person relay team but lost consciousness halfway through the swim. Rescuers managed to get Kudryk to one of the four New York City Fire Department boats stationed in the river, but he later died at Saint Luke's-Roosevelt Hospital Center. Kudryk was registered for another triathlon next month in Long Branch, N.J., the New York Daily News reported. Amy Martich, of Elmhurst, Ill., died Monday morning at Saint Luke's.
Triathlons are categorized by distance. Sprint triathlons typically require a 750-meter swim, 20-kilometer bike ride and five-kilometer run. Olympic triathlons (including the NYC Triathlon) involve a 1.5-kilometer swim, 40-kilometer bike ride and 10-kilometer run. In "Iron Man" triathlons, the swimming portion can be as long as 3.9 kilometers, followed by up to a 180-kilometer bike ride and a 42.2-kilometer run (the same distance as a marathon).
Despite being the first leg and covering the shortest distance in any triathlon, swimming has proved to be the most deadly. Minneapolis Heart Institute cardiologist Kevin Harris last year published a study in JAMA: The Journal of American Medical Association analyzing the results of 2,971 USA Triathlon-sanctioned events held between January 2006 and September 2008, during which 14 participants died—13 of them while swimming and one while biking. Swimmers who died were between 28 and 65 years old; 11 were men (although it is worth noting that more men compete in triathlons than women).
Harris's research found that six of the swimming deaths occurred during sprint triathlons, four in Olympic triathlons and the final three in so-called "long course" triathlons, which include Ironman events. Eight swimmers were in distress and called for assistance while five were found motionless on the water. Six of the deaths occurred during swims in the open ocean, four in lakes, two in reservoirs and one in a river. Still, Harris's research indicates that deaths are rare during triathlons—nearly 960,000 athletes participated in the events studied.
Scientific American spoke with Harris about his research, the dangers of the swimming leg and what might be done to make triathlons less dangerous.
[An edited transcript of the interview follows.]
What prompted you to study the causes of sudden death in triathlons?
We have a large registry here at the Minneapolis Heart Institute Foundation that looks at sudden death in athletes. We were aware of the death rate in marathons. However, given that the triathlon has become so popular (and we had noted some triathlon deaths), we started to look at it formally. The USA Triathlon–sanctioned races allowed us to pull out the denominator of athletes competing and thus calculate the incidence of death [at about 1.5 per 100,000 participants].
Nearly all of the deaths you studied occurred during the swimming events. Did this surprise you, given that swimming is the first leg of the triathlon and, presumably, the athletes are not suffering from the heat or from exhaustion at this point in the competition?
Yes, exactly. We were first surprised by this but I note this trend continues beyond the end of our study (also in several non-sanctioned races we did not formally look at). While at first I was surprised, it does make sense for a number of reasons: first, the adrenaline surge and pure number of athletes entering the water at the same time; second the fact that I suspect many athletes come from a background in running or other sports and may be less adept at swimming; third, swimming in a triathlon is totally different sport than doing some laps in the pool due to variability of extremes of waves [as well as] people swimming around you and on top of you; fourth, the inability to rest properly if needed (or call for help) as you could do in the marathon and bike [segments]; and, fifth, the difficulties in being noticed if the swimmer is in trouble due to the number of athletes in a body of water, which is not transparent. I think these are some of the factors that are related.
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24 Comments
Add CommentBecause one can drown.
Reply | Report Abuse | Link to thisComplete exhaustion on a bike or running leads to falling on the ground, worst case.
But they didn't drown; they had heart attacks, often due to abnormalities.
Reply | Report Abuse | Link to thisHowever, I don't buy the adrenaline argument either. Perhaps there is something inherent about swimming that can sometimes trigger the heart attack. For example, maybe the victim was holding his breath too long while swimming. Holding of breath plus exertion might put the heart in "overdrive" and trigger failure due to a pre-existing condition.
Having participated in a triathlon that involved swimming in a lake, I do agree that it is totally different from swimming in a pool. All of my training took place in the pool, but it didn't really prepare me enough. In the lake you can get disoriented, you can't see much, there can be "waves" (although probably negligible compared to ocean waves), and yes, people may kick you. All that can make you swim differently and could stress your heart in ways that you didn't train for.
I agree with NJ...there are several factors involved.
Reply | Report Abuse | Link to this(1) swimming uses the most muscle exertion in a much different environment from the pool; (2) the closeness of the other competitors often leads to unease and stress; (3) the coldness of the water puts an additional stress on the heart; (4) perhaps they arrived late at the event and were unable to warm up.....plus all the other reasons mentioned above.
I think page 2 is saying that the cardiac arrest events aren't identified as quickly in the swimming portion, thus delaying treatment. Perhaps heart monitors with big blinking lights should be issued to participants?
Reply | Report Abuse | Link to thiswrong, cardiac arrest is not a "heart attack" and cardiac arrest is usually precluded by some kind of arrhythmia or disrhythmia whereas a myocardial infarction is a blockage of blood flow in a coronary artery resulting in tissue necrosis. MIs are usually symptomatic and any trained athlete would have concerns followed up on during training when the symptoms arise. while a sudden disrhythmia/arrhythmia can be triggered during events like this and w/o intervention can lead to cardiac arrest which is a stoppage of heart function.
Reply | Report Abuse | Link to thisThanks for the clarification. The New York Times referred to both deaths in last Sunday's triathlon as due to "heart attacks", which is why I had that term in mind, but of course the NYT could be wrong!
Reply | Report Abuse | Link to thisIt would be interesting to know if Dr Harris studied whether warmup was possible prior to the event, and whether the triathletes who went into cardiac arrest had warmed up in the water before the race. Most experienced triathletes know that their heart rate and breathing steadies in the water much more quickly if they warm up first. If warmup in the water is not possible then warmup through calisthenics is a second best.
Reply | Report Abuse | Link to thisNew York Tri did much to make the swim safe. Time trial start to reduce the number entering the water at the same time, and abundant safety support on the water. The fast river made in-water warmup impossible, and the staging of athletes in pens made calisthenics impossible. Could it be that the sudden change in heart rate through not warming up is a factor?
Could it be that atheletes who would normally collapse due to heat exhaustion are prevented from over heating by the cooling effect of the water.
Reply | Report Abuse | Link to thisHmmm NID65, I agree with you. Warming up before jumping in water for a competition is a must. Further, the deaths maybe a result of over anxiety. Swimming demands each body part to work vigorously. A long bike ride and marathon long run is surely not for weak people.
Reply | Report Abuse | Link to thisSIDK - Agreed.
Reply | Report Abuse | Link to thisAbsence of warmup would not be a sole cause ... but might be significant when combined with:
- anxiety,
- instaneous transition from rest to anaerobic exercise (most triathletes sprint to first buoy),
- reduced O2 as breathing pattern is established,
- possible hypoxia due to one or more missed breaths.
Maybe there is research in another area that might link these stressors to arrhythmia. If so, then education of athletes / coaches / race directors / governing body (USAT) could be valuable.
Also interesting that the study found the only cycle/run death was due to cervical trauma, so no cardiac causes ... the athlete has already established an extended period of elevated heart rate in the swim leg.
One overlooked explanation is that competitors who complete a leg too slowly can't go on to the next leg. The different death rates among legs result from different populations of competitors. A slow completion time for the first leg is likely correlated with collapsing or death in the second or third legs, but the competitors who would have collapsed or died were prevented from continuing to compete instead.
Reply | Report Abuse | Link to thisInteresting. I wonder too if there is a false sense of comfort and tricking the brain into believing one isn't exerting himself quite as strenuously as he actually is. For example, how many times have I gone swimming and been absolutely knackered that night? I can swim for forty-five minutes without realizing how tired I am -- same does not apply to running. This is a good article, but I think there are still more questions to ask.
Reply | Report Abuse | Link to thisGood point!
Reply | Report Abuse | Link to thisWhen you are badly in need to catch a breath and someone splashes water into your mouth or otherwise prevents you from breathing, you die !
Reply | Report Abuse | Link to thisAthletes should wear some kind of automatically inflatable device that can be easily triggered to both provide floatation and to alert rescuers when they are in distress.
With respect to arrhythmia it is also known that individuals with Long QT syndrome type 1 may be prone to arrhythmia during swimming. reasons why are speculative. Unless symptomatic many of these individuals may not know they have the problem (prior articles in NY Times 2008, and Circulation have described this...lends ammunition to the debate of ECG screening of all athletes...but is unlikely given the sheer number of participants and prohibitive costs
Reply | Report Abuse | Link to thisWith respect to arrhythmia it is also known that individuals with Long QT syndrome type 1 may be prone to arrhythmia during swimming. reasons why are speculative. Unless symptomatic many of these individuals may not know they have the problem (prior articles in NY Times 2008, and Circulation have described this...lends ammunition to the debate of ECG screening of all athletes...but is unlikely given the sheer number of participants and prohibitive costs
Reply | Report Abuse | Link to thisI read this with great interest as a former high school runner, college oarsman and post college triathlete who has suffered from an arrhythmia called atrial fibrillation. Many people suffer from this in their 60's and later but many aerobic athletes, and particularly tall ones, suffer from this condition starting in their late 40's. My first episode was during a run and it hit me like a ton of bricks. You lose about 20% of your cardiac efficiency but its instantaneous so if you are pushing yourself its as if you suddenly went from sea level to 7000 feet. I suspect that if you were already anerobic during the swim leg with the excitment of starting you would have some serious problems. You can exercise with this condition but you have to pace yourself. Afib is just one type of arrhythmia and others could have the same effect. I also think there is a postural aspect to Afib which happens more often when I am prone than standing up.
Reply | Report Abuse | Link to this"many athletes come from a background in running or other sports and may be less adept at swimming"
Reply | Report Abuse | Link to thisI think this is the most likely explanation.
I used to training buddy an iron-man for his cycling leg. He was 6'4" and 95kg with huge neck and shoulders. I was 6'3" and 58kg with a chest like a squashed chicken. I could ride faster than him, particularly uphill and keep up with him when running. He used to encourage me to get into triathlon, but I noticed that being quick on a bike and running is not sufficient to make up for insufficient strength in swimming. If you look a the physique of good swimmers, they are the classic triangle upper body shape. Good long distance cyclist and runners rarely have much upper body strength - it's this weight saving that makes them fast.
Waves
Reply | Report Abuse | Link to thisHaving nearly died once when swept by a fast, cold river current into deep water, I can only suggest that it's the rapid acceleration of heart beat from near-normal levels that contributes to cardiac arrest in these triathlon events. Also, there's no comparison (and little preparative conditioning) in the pool training situation. Pool training is a "warm up" activity which avoids the emergency start-up of rapid heart beat encountered in "scary situations" and triathlon swimming races.
Reply | Report Abuse | Link to thisI've never seen a scientific comparison of heart rates in swimming compared to other vigorous activities - but I do know that swimming uses more muscle groups simultaneously than most other activities. It just follows: supplying blood *suddenly* to all skeletal muscle groups has got to put a great load on the heart.
The biggest clue comes from the fact that the most common situation for cardiac arrest in normal activities is taking a crap. Apparently when straining on the toilet, the sudden rise in blood pressure is transiently more than the cardiac muscle can cope with, leading to some failure in conduction or contraction.
Reply | Report Abuse | Link to thisIn triathlon, plunging into water colder than air, the situation is similar: peripheral circulation clamps down fast to prevent a loss of body heat; this leads to a sudden increase in blood pressure. Combined with sudden exercise of most muscle groups in a swim start, and holding one's breath to avoid taking in water of the splashing around you, plus the normal mammalian reflex when encountering water (slowing breathing and heart rate when water hits your face) and the time delay in rescue, it seems to me that transient high blood pressure resulting is the most likely cause of fatalities in triathlon.
Perhaps the reason the most people suffer cardiac arrest during the swimming leg is precisely because it is the first leg of the triathlon, and causes cardiac arrest in susceptible individuals before the next two legs get a chance to do it. If people started the triathlon with long-distance running rather than swimming, that might become the leg with the most fatalities. To paraphrase Scrooge, if they are like to die, let them get on with it and decrease the competition!
Reply | Report Abuse | Link to thisI have unfortunately been in 2 triathlons in the past couple of years in which someone died during the swim, one of which was this past weekend. Both victims were males in their mid 40s, which might point to LAD or the widowmaker artery, which can often be largely asymptomatic and, when the MI occurs, has a very low survival rate. I spoke to the first responders, and time to rescue was not a causal factor since both were reached quickly. Safety personnel are significantly closer to the athletes during the swim than on any other part of the triathlon. I do think that the adrenaline and cold water of the swim leg pushes pulse rates to the limit, even higher than other parts of the race, and causes these MIs. Also, as Ramil points out, it's the first leg.
Reply | Report Abuse | Link to thisThis is really unfortunate to read. There are some things that may help. Warming up is very important for a triathlon. So is getting one's anxiety under control before the race. Lastly, always practice a lot in the open water and anticipate the crowds. The "freak out factor" may be a lot of what is going on with sudden deaths.
Reply | Report Abuse | Link to thisAnd, just to mention, this isn't just a swimming-related thing. Sudden deaths have been reported in marathons and other endurance-related sports.
Kevin of http://triswimcoach.com