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Munatones
September 18th, 2010, 08:17 PM
Of all the open water swims around the world, is there a race where there is a maximum allowable water temperature? If so (or if not), what is the scientific information or medical guidelines for a maximum allowable water temperature for open water swims (non-wetsuit)?

chaos
September 18th, 2010, 10:48 PM
interesting question.
i know of a few lakes in the south that have had incidents of deadly brain eating amoeba at temperatures above 80 F. other than that, i would think that air quality would be an important factor in determining weather a "warm water event" would pose a risk to the safety of swimmers.

orca1946
September 20th, 2010, 06:35 PM
WOW, never even thought of that - always cold comes to mind in Chicago.

drmdive
September 22nd, 2010, 09:14 AM
Interesting question. I think the responses will be different based on where people live and train. I live in the Sarasota/Bradenton area in Florida and I train in the Gulf all summer where water temps get into the upper 80s with air temps in the mid 90s. Hot conditions, but we adapt. Even some of the outside pools in the area that aren't chilled can get into the upper 80s during the summer. Training in those conditions is tough and not very enjoyable but a must if you want to train all summer long.

We had someone visting our area from San Diego. They did an OW training swim with our masters group a few weeks back and had a hard time in the hot water. He just wasn't use to it.

For me, the concern is always how cold the water is. The coldest 5k I did had water temps of around 69-70, which for me was pretty cool. For many of you, that's more like bath water. Anything below 65 would make me nervous since I have no experience in that cold of water.

Ken Classen
September 22nd, 2010, 11:20 AM
Interesting question. I think the responses will be different based on where people live and train. I live in the Sarasota/Bradenton area in Florida and I train in the Gulf all summer where water temps get into the upper 80s with air temps in the mid 90s. Hot conditions, but we adapt. Even some of the outside pools in the area that aren't chilled can get into the upper 80s during the summer. Training in those conditions is tough and not very enjoyable but a must if you want to train all summer long..

I'm from Colorado and did the USMS 10K OW Championship in Indiana this year. Water was 85F, which was not a benefit for me. I was able to swim but felt like I couldn't race as I just became to warm. However, many of the locals and folks who trained at the event site or OW in the area seemed much better adapted.

I'm curious on what you think the water temps will be for the USA/USMS OW Championships in Ft. Meyers, FL on June 10-12, 2011 will be? I'd like to do the race but if it's going to be over 80F again it may difficult to get excited about. http://www.openwaterfestival.org/

It would be interersting to get some science behind this, maybe USA/USMS swimming & UST (triathlon) need to pony up a grant for a little research in the area.

E=H2O
September 22nd, 2010, 11:31 AM
Ok I'm a shill, but my favorite swim blog is www.offthedeck.net, she even spent the $1.95 to get her very own web domain.

Well Ken I took a couple of moments and went to your favorite swim blog: offthedeck. After reading this I can understand why. A very scientific and systematic approach to training.

"Brownies were not a random choice, but a process of elimination end-result. Here’s the breakdown:
1) brownies are yummy
2) brownies are crowd-pleasers
3) brownies can easily be made from scratch
4) brownies can be made simple or elaborate
5) brownies offer endless variation per batch via batter, mix-ins, etc.
6) brownies can easily be decorated or embellished
7) brownies can be “healthy-ed up” without sacrifcing taste or texture"

Ken Classen
September 22nd, 2010, 03:39 PM
Well Ken I took a couple of moments and went to your favorite swim blog: offthedeck. After reading this I can understand why. A very scientific and systematic approach to training.

"Brownies were not a random choice, but a process of elimination end-result. Here’s the breakdown:
1) brownies are yummy
2) brownies are crowd-pleasers
3) brownies can easily be made from scratch
4) brownies can be made simple or elaborate
5) brownies offer endless variation per batch via batter, mix-ins, etc.
6) brownies can easily be decorated or embellished
7) brownies can be “healthy-ed up” without sacrifcing taste or texture"

I told her I was disappointed she didn't mention "medicated brownies" ;)

drmdive
September 22nd, 2010, 03:55 PM
[QUOTE=Ken Classen;226672]I'm curious on what you think the water temps will be for the USA/USMS OW Championships in Ft. Meyers, FL on June 10-12, 2011 will be? I'd like to do the race but if it's going to be over 80F again it may difficult to get excited about.QUOTE]


The water temps will definitely be in the 80s, probably lower 80s though, unless the lake is spring fed. If so, it could be cooler.

E=H2O
September 22nd, 2010, 04:00 PM
[QUOTE=Ken Classen;226672]I'm curious on what you think the water temps will be for the USA/USMS OW Championships in Ft. Meyers, FL on June 10-12, 2011 will be? I'd like to do the race but if it's going to be over 80F again it may difficult to get excited about.QUOTE]


The water temps will definitely be in the 80s, probably lower 80s though, unless the lake is spring fed. If so, it could be cooler.

YUK!

Lump
September 22nd, 2010, 04:19 PM
Well, according to our boat captain, the water temp at the official "Swim around Key West" in June was 91. I would NOT recommend that to anyone! I did only 4.5 mile on a 3-man relay.....I could not wait to get out. I don't know how the solo swimmers did it, I really don't. Most of my OW swims are in 80-86 here in the SE.

Ken Classen
October 25th, 2010, 12:42 PM
Local officials said all safety measures were in place for the race, but the race's winner, Germany's Thomas Lurz, said that it was far too hot to hold the competition. "The water was amazingly hot," Lurz said in a statement. "There were many swimmers who had serious problems in the water." Maddy Crippen said that her brother had never been in better shape. "My brother prided himself on being a specimen of excellence," she said with a quiet laugh. "He was at the height of his physical fitness." Several swimmers complained of dehydration and disorientation after swimming in the warm water and three were taken to the hospital. The UAE Swimming Association said the water was 84 degrees at the start of the race, but many swimmers have come forward to insist it was more like 90 degrees. http://abcnews.go.com/Health/fran-crippens-sister-swimmer-voiced-safety-concerns/story?id=11961795

In light of the Fran Crippen tragedy, I think this thread needs to be resurrected. If FINA doesn't act quickly with research on this subject I hope that USMS, USA Swimming and some of the Triathlon organizations will. Regarding the UAE swim association on the temperature. I know race promoters are under a lot of pressure to make sure an event happens. I have heard many rumors in the Triathlon community where race directors drop there thermometer in deep part of the lake or somewhere they know it's cooler so entrants can continue to ware there wetsuits. With strong growth of open water swimming and triathlon, this issues needs to be addressed now and firm guidelines put into place. It's so sad that it had to come to his.

Hoosier
October 26th, 2010, 04:26 PM
Ken, Amen

swimthegoodfight
October 26th, 2010, 05:51 PM
The length of the race will be critical too obviously.

Highly-trained and highly-competitive athletes might be at greatest risk in the case of temperature extremes.

I didn't know Fran Crippen but I presume, and I intend this to be a a very high compliment, he didn't know the meaning of the word 'quit.' He was also accustomed to working himself at the absolute highest level of endurance and tolerance. How could he know his body might fail him?

I think the powers that be are keeping details of the race very hush-hush... were there water stations? were the swimmers made to drink water?

God bless Fran and the Crippen family - our thoughts and prayers are with you.

srcoyote
October 27th, 2010, 02:51 PM
Another dynamic in higher water temperatures is mandatory cap wear. I recognize the need for brightly colored caps in open water swims, but if I get in water over 85, wearing a cap holds in too much heat. I get headaches swimming any further than 500 yards.

E=H2O
October 27th, 2010, 03:04 PM
Another dynamic in higher water temperatures is mandatory cap wear. I recognize the need for brightly colored caps in open water swims, but if I get in water over 85, wearing a cap holds in too much heat. I get headaches swimming any further than 500 yards.

I've had my cap "accidentally" come off in the middle of a race. Never been DQ'd for it.

jim clemmons
October 27th, 2010, 04:36 PM
Another dynamic in higher water temperatures is mandatory cap wear. I recognize the need for brightly colored caps in open water swims, but if I get in water over 85, wearing a cap holds in too much heat. I get headaches swimming any further than 500 yards.

I generally won't race in pool meets over 400m/500yds with a cap due to heat overload and that's usually around 79/81*F. Occasionally, if the water's around 77/78*, I may attempt up to a 800m/1000y.

beksurf
October 27th, 2010, 05:05 PM
The length of the race will be critical too obviously.

Highly-trained and highly-competitive athletes might be at greatest risk in the case of temperature extremes.

I didn't know Fran Crippen but I presume, and I intend this to be a a very high compliment, he didn't know the meaning of the word 'quit.' He was also accustomed to working himself at the absolute highest level of endurance and tolerance. How could he know his body might fail him?

I think the powers that be are keeping details of the race very hush-hush... were there water stations? were the swimmers made to drink water?

God bless Fran and the Crippen family - our thoughts and prayers are with you.

I agree... I am in no way an athlete of Fran's status but I just recently competed in an event that I should have been pulled from the race. They did enforce stops and in my case the water temp was too cold not too hot but... I didn't pay attention or allow them to pull me from the race. At one point they took my temperature and said it was 87. I just looked at them - shaking because I was shivering so bad and having people feed me because my fingers wouldn't work enough to peel bananas - and I said that I was finishing the race. Then a couple of stops later they went to check my temperature again and I wouldn't even let them.

In hind site... I really shouldn't have pushed myself to that extreme. I was lying to people to continue swimming to finish the challenge.

I hold myself responsible in this swim because I should have known better but... all it takes is one person to think they can keep pushing it when the signals are clearly demonstrating to others that they shouldn't. Had someone asked me any questions that required thought other than what my name was I am sure I wouldn't have been able to answer correctly.

I know its extremely hard to make the decision to pull an athlete from their race but... it makes me wonder how lucky we just have been so far with all of this...

chaos
October 27th, 2010, 06:43 PM
[QUOTE=beksurf;228944 At one point they took my temperature and said it was 87. I just looked at them - shaking because I was shivering so bad and having people feed me because my fingers wouldn't work enough to peel bananas - and I said that I was finishing the race. Then a couple of stops later they went to check my temperature again and I wouldn't even let them.
[/QUOTE]

87 is moderately hypothermic. i think a memo should have gone out for those not experienced with swimming in those temperatures advising them to have their kayaker equipped with sufficient warming gear. i also understand that there were no attire restrictions and indeed saw photos of swimmers with gloves, thermal hoods, full wetsuits, etc.

another safety measure would be to have all participants show documentation of a long qualifying swim at a prescribed temperature... many marathon swims do require just that.

aurora
October 27th, 2010, 09:08 PM
I think the whole water temp thing should be looked into more, I was very uneducated about body temp and what is to hot or to cold. It was not till recently I went on a training swim with 2 friends in wet suites I was not in one. The water temp was 54. We did an hour and at the end my speech had gone and could not stand or feel from the wast down for 20 min even after being out of the water. Its so hard because as swimmers we really want to always be strong. But i think this case I was plan poor judgment. Water temp high or low never used to freak me out. But now i can say i think more about being smart. It would be nice to have more education to swimmers at events about the effects of water temp on the body. I think then maybe people will know the sings and swim smarter and get out of a race if they know the effects.

sdswimmer
October 29th, 2010, 12:47 PM
Its always a tragedy to have an athlete die and it happens in most sports I can think of but if we are 100% protected from risk is it still sport? I am worried that there is too much pressure to make things safe which would eliminate most of the open water venues now in use. I have more questions than answers and pose them here to see what the rest of you think.
If open water is restricted to only conditions safe for everyone we will have very few races, temps in the 60's are too cold for some, for others 75 is too warm. Should we eliminate rough seas, winds etc. There’s already too much pollution and toxins such as blue-green algae and industrial runoff that reduce possible venues.

I feel that the challenge of open water is to understand and prepare for the likely conditions in the events you plan to participate in and to choose events that will work together for your training. It would not be reasonable to prepare for a cold swim like the 12.6 ocean challenge to be followed by a warm swim such as the world's or Pennock Island Alaska then the Maui Channel Hawaii. Time is needed to acclimate to each condition and the harder you will swim the more carefully you must acclimate.

Its being claimed by some that this information was not available, perhaps there's not enough science behind it but I do recall Dr. Miller (USA team) speaking about hyper and hypo thermia and he told us you should have (an ideal of at least) two weeks for adaptation in either direction. There has been more fear of cold than warm water expressed by swimmers I am in contact with but I suppose this will now change.

Are risks understated or are athletes over confident? What kind of safeguards should be in place and what would eliminate open water from sport altogether? Should there be qualifiers for each condition? Should there be “observers” for each person in a race? What would that mean for your local 1k or 5k? Is it a question of what’s too hot or cold to hold a race or how well athletes are informed before they sign up for that race? Should nationals, worlds etc have less extremes than local events?

jadie
October 30th, 2010, 12:40 PM
Runners are pulled from marathons for medical reasons. Period they do not have a choice. They have medi stations. The duration not just the distance need to be addressed. Regardless of water temp. Blood pressure, pulse, and body core temps should be checked. If an athlete is in trouble, they may have lost the ability to make a sound judgement. Fran was dedicated. But he had his whole life in front of him. If he were aware of his serious condition, I believe he would have chosen to get help. This also begs the serious question of education for the athletes, event sponsors, and Fina. We are still in new territory with so many swimmers competing unattended. This is a tragedy that should never happen again! One other point. Every athlete is different in their tolerance of water temps. That is why THEY NEED TO BE monitered. We can all feel better thinking that Fran would have wanted to go this way. I disagree. He would have wanted to live.

firefly
October 31st, 2010, 03:31 AM
I agree that while perhaps there should be upper and lower limits on water temps, re warm water at least: air temperature must ALSO be a factor. When swimming, the effects of the sun are no less and even more than when not in the water. During a 21k swim in Lake Tiberias in June, one guy suffered headaches until he donned a swimming cap, and protected his head from the sun.
The signs of heat exhaustion are known among runners, but as it's apparently less common among swimmers, it's apparently less recognized. When someone suffers heat exhaustion, they lose their sense of judgement and it's up to people around them to pull them out of the race and provide treatment. I understand the same is true of hypothermia. And both situations can lead to permanent damage and/or death if not caught and treated in time.
Any race in extreme conditions hot or cold, should have extra help on land and water to identify and aid those who for whatever reasons can't deal with the extreme conditions.

swimthegoodfight
October 31st, 2010, 03:05 PM
jadie - for example, I understand the need for kayak escorts in some cases but as a swimmer that has participated an open water swims as destination events, I would rather not pay for a kayak or vessel escort unless I consider it necessary...

I participated in several events requiring kayak support - sometimes they were simply good sense, e.g Pennock Island 8-Mile Swim... others superfluous, e.g. Lake Travis Dam 5K

How should all saltwater open waters react if a participant is taken by a shark? in a sense, the appropriate reaction might be NO open water events in saltwater... as a proponent of open water swims, seems like closing all beaches might be appropriate too!

it likely would have been helpful to participants at the recent FINA event if there had been mandatory water stops... swimmer condition could have been assessed at each water stop - however this doesn't seem much like a race.

It isn't presumptious to think Fran would like to be with us... his family would like him with us. I believe too that Fran, and all of us, swim at our own risks - several actions ought to be considered to reduce risks - but these are dependent on swim length, distance from shore, wind conditions & chop, and water & air temperatures.

there are many more parameters impacting success, e.g. athlete'e conditioning, but firstly we all must realize we swim at our own risks.

the persons responsible for implementing new regulations will mostly have zero swimming and open water experience - it will be legislators and liability insurance issues - ultimately the final outcome is we will have fewer, and more expensive, open water swim races.

E=H2O
October 31st, 2010, 03:32 PM
I have participated in many activities over the years. All of them had different levels of risk. Athletes are entitled to a reasonably safe safe environment to compete, but what is reasonably safe in one environment (a pool) is significantly different from another environment (Pipeline surf competition - ok so I never did that one). When I climb in the mountains I assessed risk and made my decisions accordingly. When I would go out in the wilderness alone in a national park I assessed the conditions and made a decision to go. I didn't want the national park telling me I couldn't. But I did my homework, assessed the risk and decided if I could manage the risk. I could not eliminate all of it but I could reduce risk.

In a race where you are relying on organizers to provide a certain level of safety, they should be held to their responsibility. So the question is what level is that. If you are racing in open water in the ocean you have to expect the possibility of jellyfish & sharks. There is nothing the organizers can do about that. But if the organizers announce that they have people stationed around the course and if you have problems just raise your hand and someone will come to your assistance, and then don't, well they failed in their duty. The swimmer relied on their presence when assessing risk, and justifiably so. If someone goes under and the organizers don't see them, then the presumption is they have failed to put in place the level of protection that they agreed to assume, and which the swimmers relied on. That's negligence plain and simple.

jadie
October 31st, 2010, 05:47 PM
That is a great message. The word reasonable will likely get a new definition. Every post makes great points. This will be a difficult journey for all involved, and I would hope they would seek the council of open water experts.

orca1946
November 9th, 2010, 12:48 PM
FINA has it's fingers in all other stuff, noe ma be the time for them do look into this!

GlidingOnGlass
November 15th, 2010, 01:00 PM
Well, according to our boat captain, the water temp at the official "Swim around Key West" in June was 91. I would NOT recommend that to anyone! I did only 4.5 mile on a 3-man relay.....I could not wait to get out. I don't know how the solo swimmers did it, I really don't. Most of my OW swims are in 80-86 here in the SE.

I swam the solo, and I have to say that whatever the water temp was it should be considered beyond the range of what is allowable for a multi-hour competition. I thought the temp was higher than 91, though, that number seems a bit low but you measure was probably more official than the temps that were quoted to me. I experienced heat exhaustion symptoms around mile 10. I can easily see how someone might pass out under those conditions.

swimthegoodfight
November 16th, 2010, 04:51 PM
Hypothermia and afterdrop following open water swimming: The Alcatraz/San Francisco swim study*1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W9K-45WGG86-Y&_user=952833&_coverDate=10%2F31%2F2000&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543675280&_rerunOrigin=scholar.google&_acct=C0#m4.1)
Thomas J. Nuckton MD*, David M. Claman MD*, Daniel Goldreich PhD†, Frederick C. Wendt MD* and John G. Nuckton MD*
From the *Division of Pulmonary and Critical Care Medicine, and the Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA; and the Rangos School of Health Sciences, Duquesne University, Pittsburgh, PA.

Received 19 November 1999;
revised 3 January 2000.
Available online 22 May 2002.




Abstract

To determine whether or not participants in open water swim events experience hypothermia and afterdrop, rectal temperature was measured for up to 45 minutes in 11 subjects following the New Year's Day Alcatraz Swim. This event was held in open water (11.7°C [53.0°F]) in the San Francisco Bay, and participants did not wear wetsuits or other protective clothing. Biophysical parameters, including surface/volume ratio, body mass index, and percent body fat were measured before the swim, and statistical analysis was done to determine predictors of temperature decrease and afterdrop duration. Applying the American Heart Association definition of hypothermia (less than 36.0°C [96.8°F]), hypothermia was seen in 5 of the 11 subjects. Using a more rigorous and traditional definition (less than 35.0°C [95.0°F]), hypothermia was seen in only one subject. Afterdrop, defined as continued cooling following removal from cold stress, was seen in 10 of the 11 subjects. Surface/volume ratio (S/V) and body mass index (BMI) predicted the lowest recorded temperatures (P < .05; r(S/V) = −.71, r(BMI) = .72) and afterdrop duration (P < .05; r(S/V) = −.75, r(BMI) = .69). These results suggest that hypothermia and afterdrop can occur commonly after recreational open water swimming, and that participants should be observed for signs of temperature decrease following removal from cold stress. (Am J Emerg Med 2000;18:703-707.

swimthegoodfight
November 16th, 2010, 05:04 PM
Hypothermia Is a Significant Medical Risk of Mass Participation Long-Distance Open Water Swimming
Domhnall Brannigan MBBCh, BAO BA1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#aff1), 1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#fn1), Ian R. Rogers MBBS, FACEM1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#aff1), 1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#fn1), Ian Jacobs PhD, FRCNA2 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#aff2), 1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#fn1), http://www.sciencedirect.com/scidirimg/entities/REcor.gif (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#cor1), http://www.sciencedirect.com/scidirimg/entities/REemail.gif (Ian.Rogers@health.wa.gov.au), Amanda Montgomery MBBS1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#aff1), 1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#fn1), Aled Williams MBBS, FACEM1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#aff1), 1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#fn1) and Nicole Khangure MBBS1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#aff1), 1 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B9HBY-4YBKYSN-3&_user=952833&_coverDate=03%2F31%2F2009&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_searchStrId=1543676738&_rerunOrigin=scholar.google&_acct=C0#fn1)
1 Sir Charles Gairdner Hospital, Nedlands, WA, Australia
2 Sir Charles Gairdner Hospital, University of Western Australia


Available online 8 February 2010.




Objective

To document the prevalence of hypothermia in a mass participation endurance open water swimming event and to determine demographic and individual factors that may predict failure to finish the race and hypothermia.
Methods

A prospective observational study in competitors in a 19.2-km open water swimming race in Perth, Western Australia. Pre-race information collected included age, sex, training and race experience, medical history, and body mass index (BMI). Body temperatures at 5 minutes postrace were measured using an equilibrated oral- or rectal-reading low-range glass mercury thermometer. Logistic regression was used to develop models predicting hypothermia (defined as a temperature of <35°C) and failure to finish the race.
Results

One hundred and nine competitors (70 male, 39 female) with a combined mean age of 38.4 ± 12.1 years were studied. Hypothermia was the most common race-related illness, identified in 26 of 35 swimmers screened as requiring temperature measurement, including 5 who required short-stay hospital care and 2 who required critical care transfer. Longer race duration (odds ratio [OR] 1.77, 95% CI 1.10–2.84, P = .018) was associated with an increased risk of hypothermia, and higher BMI (OR 0.57, 95% CI 0.41–0.79, P = .001) was associated with a decreased risk of hypothermia. Weak predictors of failure to finish were age (OR 1.06, 95% CI 1.01–1.11, P = .012) and hours spent training (OR 1.08, 95% CI 1.01–1.16, P = .025).
Conclusions

Hypothermia is a common condition affecting mass participation long-distance open water swimmers. Increased BMI appears to be protective against hypothermia, while prolonged duration of the swim predicts an increased risk of hypothermia. The weak predictors of failing to finish are of questionable clinical significance.


Key words: hypothermia; open water swimming

E=H2O
November 16th, 2010, 08:20 PM
I guess I am going to eat a lot more ice cream and fatten up now that it has been scientifically proven. :-)

swimthegoodfight
November 16th, 2010, 09:20 PM
the alcatraz study I found entertaining reading...

the headline of study 2? really? who would of thought?