Monday, December 14, 2009

Why do some swimmers cark it?

Gidday to our ocean swimming friends from the other side of the ditch (or "dutch" to use the correct Kiwi pronunciation)
I did the Russell to Paihia swim in the Bay of Islands and met Paul and a few other folk there. Just before the swim began we were talking about why some people pass away during swims. This is a serious topic of conversation and, as a High School Science Teacher, I have a hypothesis as to why some of the fatalities occur on the finish line. My hypothesis goes as follows:
Swimming is quite tough and it is pretty fair to assume that the heart rates go quite high. When the finish line comes in sight, some swimmers are tempted to give it a bit of "grunt" for the last little bit. This puts stress on an already hardworking heart. Then, at the end, the swimmer changes her or his body posture from horizontal to vertical as they leave the water and this puts the head about a half a metre above the heart instead of at the same height. The implication of this is that the blood pressure to the head drops (hence the dizziness we feel when we exit the water) and the heart has to work harder (when it might already be a maximum). I think this might be a causal factor in some of the deaths at the finish line. I have no ability to test this hypothesis but I thought I'd advance it for further discussion and perusal, possibly by medical researchers who could investigate further.
If a bit of email "chatter" can contribute to a possible reduction in the number of deaths then it is worth bouncing these ideas around for a bit.
Cheers and thanks
Tony ("Haggis") Henderson
a non-wetsuit swimmer from NZ


We met Haggis at the start of the Bay of Islands swim in Russell on Saturday. Talk about personality filling a void! But we also know that his contribution is inspired by the knowledge that the NZ ocean swim series has lost four swimmers in the last four years: one each year. This can happen, of course, and we are lucky that we haven't had similar issues in Stray'a. But that's what's behind it: os.c

8 comments:

  1. I was told ... Cool down after strenuous exercise - very important - 10 minutes of slow aerobic exercise (slow swim or walking) to allow the body to adjust. Otherwise increased risk of light-headedness, fainting or worse if strenuous exercise is suddenly stopped.
    The messenger Pheidippides dropped dead after running from Marathon to Athens in 490BC. A bottle of sports drink every 40 minutes and a long slow aerobic cool-down after the run might have saved him. Not sure that would fit well with the legend though.

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  2. I have read discussion that the reason there are people dying on the finish line are largely due to the wearing of wetsuits when its unnecessary. Their body is trying to cool itself down and the wetsuit is trapping the heat in, causing their body to overheat and putting extras stresses on their heart and all their other bits.

    Take that you wetsuit wearing triathletes!

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  3. The hypothesis seems to make sense, but am I missing something at the finish of the oceans swims, "I think this might be a causal factor in some of the deaths at the finish line", must have missed those swims, or too slow and the affected persons were already on their way to hospital.
    David Helsham

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  4. I see os.c has added a comment, apparently they lose on average one swimmer a year in the NZ OW series. I don't like those odds. I'm never doing an ocean swim in New Zealand!!!

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  5. Richard, I lived in NZ for 8 years, come winter rugby time, and the Bledisloe Cup, I was no better than a mangy dog.
    I can only presume from above discussion, that Australian ocean swimmers, both male and female are that more fitter, handsome/beautiful, faster, and more intelligent than our friends from across the ditch, (hats off to the All Blacks, I must acknowledge their prowess). And apart from anal triathletes, most of us do not wear wetsuit.
    David

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  6. forget the worry of karking it, would you rather die swimming doing something you enjoy grumbling about or die with spittle running down your chin in the old gits home.
    The real concern is where can I get the sauce the over 40 year olds are using. one 45 year old tells me he is too sick to train and than does a very quick time at billy. One 56 year old no longer swims in the 50 plus but swims in the elite instead.
    Can anyone tell me where I can get this performance enhancing sauce.

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  7. Nothing to do with wetsuits or the finish line people. I was in the race in Auckland when the last chap died- near the start. New Zealand has a different culture of participation in all manner of events- such as ocean swims- and as a result less fit people still have a crack.

    I am an Aussie who just moved to New Zealand this year, from Queensland where I was a regular race participant. Trust me, when races started here in early November, a wetsuit was a must. Not necessarily from the perspective of the cold water, for yes it was cool and still is, its just that you can't be cometitive without one. Simple fact. Even though I detest wetsuits.

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  8. it has more to do with the return of blood to the heart,as you swim along you don't have normal vertical posture and no muscles in your legs pumping blood up to your heart,in most of us the heart is easily capable of managing the various stresses on the heart specifically but if the wiring is off and the ability to respond is altered then the contraction is not so good so lots of things can go wrong the ventricles can "fibrillate" and get out of sync with the rest of the heart and stop

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