Dead man (swimming)

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Assistance in learning the "starfish" in swimming lessons.

In connection with swimming and in particular the water used for swimming beginners, dead man describes a position of full-body floating, in which swimmers float flat on the surface of the water with little or no movement of arms and legs. In order to relieve children of possible reservations and fears, alternative terms such as starfish or water lily are now used for “dead man” in children's swimming .

It is often helpful to relax and stretch your limbs flat below the surface of the water. The head is almost completely covered by the water; Nose and mouth opening remain above water.

Usually the legs are heavier and tend to sink. Women often find it easier to float because the majority of the less dense body fat is in the hip area and can compensate for the higher density of the legs, while the fat tissue in men tends to be a little higher in the abdominal area, which means that the body's center of gravity and the center of volume are further apart. If necessary, this can be compensated by stretching your arms above your head and pulling your legs up. The lowering of the legs can also be prevented by a light crawl kick and the dynamic buoyancy this creates.

Physics and Physiology of the Dead Man

Bathers in the Dead Sea : Salty water has a higher specific density and therefore makes the body more buoyant when swimming.

The swimming exercise is made possible by the buoyancy of the human body, which, however, due to the different specific densities of the fat, muscle and bone content, can differ individually and depending on age. The buoyancy of the human body is different depending on the salinity of the water, so that the dead man can be more easily practiced in salty water, especially in the Dead Sea . Comparable with the dead man in the context of water sports, there is also the so-called floating as a therapeutic relaxation technique in specially made floating pools with high salty water.

With the exception of adipose tissue, body tissue and especially bones, cartilage and tendons are heavier than water. The buoyancy is usually only made possible by the chest, which is filled with air when breathing. In a Spanish study, only 8% of the female and 1% of the male subjects floated on the surface of the water after exhaling.

The body of a percentage of the population has a density that is greater than water, even when the lungs are full, which means that floating in water without moving the limbs is not possible. The cause is often increased bone mass or density . A US study found that 8% of subjects with European ancestry also sank with filled lungs, while this was the case for 67% of subjects of African descent. This is attributed to a higher bone density, a lower fat content and an average of up to 20% less lung volume.

Water habituation and survival technique

In swimming lessons, full-body floating exercises are particularly important in two cases: As part of getting used to the water, they can help overcome fears and contribute to a more relaxed swimming posture. Even with advanced swimmers, they should help - for example according to the swimming teaching method " Total Immersion " - to practice a better balance to improve swimming techniques such as the crawl .

On the other hand, dead man is considered a survival technique against drowning. Babies and toddlers taking baby swimming lessons can use dog paddling to get around underwater. However, they are not yet able to lift their heads out of the water using dynamic buoyancy in order to breathe . That is why in the USA a so-called back float is trained in some courses as a survival technique for toddlers or even babies. They learn to turn on their backs, take a breath or call for help. However, there is a caution against teaching this technique before the required age using methods that cause children to breathe or swallow significant amounts of water, which can be traumatic. In addition, there is a risk that parents will feel a false sense of security if they rely on appropriate training as - possibly the only - precaution against drowning. The American Academy of Pediatrics revised its warning against swimming lessons under four in 2010, but remains concerned about self-rescue courses for children under 12 months of age. The dead man can also save adults from drowning in a state of exhaustion until help can be called for. Often the prone position is recommended for this, with short swimming movements only to take a breath.

Phrase

Derived from this swimming figure, there is the phrase play dead man or give the dead man , when someone is uninvolved in a situation or evades responsibility.

Web links

Individual evidence

  1. ↑ Simone Richter: Swimming has something to do with courage. Interview with sports scientist Dr. Lilli Ahrendt on the subject of children's swimming ( Memento of the original from February 1, 2014 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. In: Mobile. The parents' magazine for kindergarten in 2008. @1@ 2Template: Webachiv / IABot / www.mobile-elternmagazin.de
  2. ↑ However, the term “dead man” continues to be used alongside numerous other expressions such as angel, eagle or, as I said, starfish, Ursula Wendel: water habituation, water agility, water coping. In: Cornelia Glatz, Nico Moritz, Ursula Wendel: SVW swimming coach assistant. Training manual. Published by the Wuerttemberg Swimming Association, BoD - Books on Demand, 2011, ISBN 3-8423-8265-0 , p. 39.
  3. ↑ a b c LLANA-BELLOCH S., LUCAS-CUEVAS AG, PÉREZ-SORIANO P., PRIEGO QUESADA JI: Human body flotation and organic responses to water immersion . Research Group in Sport Biomechanics - GIBD (GIBD) and Department of Physical Education and Sports . University of Valencia, Facultat de Ciències de l'Activitat Física i l'Esport. C / Gascó Oliag, 3. 46010. Valencia, Spain. Journal of Physical Education and Sport (JPES), 13 (3), Art 57, pages 354 - 361, 2013 online ISSN: 2247 - 806X; p-ISSN: 2247-8051; ISSN - L = 2247 - 8051. Published on the Internet on September 30, 2013. DOI: 10.7752 / jpes.2013.03057
  4. ↑ Nadja Schäfers: Holistic development support through baby swimming in the 1st year of life: A multimedia learning software for parents and prospective course instructors , GRIN Verlag, 2010, ISBN 3-640-61041-5 , p. 49 f.
  5. ^ Annette Gasper: Swimming: The entry into the crawl technique. ( Memento of the original from October 24, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.tri2b.com
  6. ↑ Irving P. Herman: Physics of the Human Body Biological And Medical Physics. Springer, 2008, ISBN 3-540-29603-4 , p. 431.
  7. ^ Gregson CL, Steel SA, O'Rourke KP, et al .: 'Sink or swim': an evaluation of the clinical characteristics of individuals with high bone mass. Journal Osteoporos Int./ Osteoporosis Int. , 2012 Feb; 23 (2): 643-654. Published online 2011 Apr 1. doi: 10.1007 / s00198-011-1603-4. PMCID: PMC 3261396 (free full text). PMID 21455762
  8. ↑ Terry Laughlin: Total Immersion: The Revolutionary Way To Swim Better, Faster, and Easier. Touchstone, 2012, ISBN 1-4516-8833-4 , pp. 105 ff.
  9. ^ A b Suzan Clarke, Sabrina Parise: Toddler Swim Training Not Taboo, Doctors' Group Says . ABC News dated June 18, 2010.
  10. ↑ http://www.babyswimming.com/FAQ.htm
  11. ↑ Alicia Bayer: Expert warns of the dark side of survival swimming programs . In: Examiner.com, July 22, 2010.
  12. ↑ "Please don't play dead man!" . Stuttgarter Zeitung, December 31, 2011. Accessed May 23, 2019
  13. ↑ Dead man . heise online, October 18, 2017. Retrieved May 23, 2019