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Freediving

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Free-diver with monofin, ascending.

Free diving is any of various aquatic activities that share the practice of breath-holding underwater diving. Examples include breathhold spear fishing, free-dive photography, apnea competitions and, to a degree, snorkeling. The activity that garners the most public attention is competitive apnea, an extreme sport, in which competitors attempt to attain great depths, times or distances on a single breath without direct assistance of a self-contained underwater breathing apparatus (scuba).

Overview

Free-diving is a technique used with various aquatic activities. While in general all aquatic activities that include breath-hold diving might be classified as a part of free-diving, some sports are more accepted than others. Examples of recognized free-diving activities are (non-) competitive free-diving, (non-) competitive spear-fishing, free-diving photography and mermaid shows. Less recognised examples of free-diving include, but are not limited to, synchronised swimming, underwater rugby, underwater hockey, underwater hunting other than spearfishing, and snorkeling. The discussion remains whether free-diving is only a synonym for breath-hold diving or whether it describes a specific group of underwater activities. Free-diving is often strongly associated with competitive breath-hold diving or Competitive Apnea. It is a sport in which competitors attempt to attain great depths, times, or distances on a single breath and without the assistance of breathing apparatus like SCUBA. The following remainder of this article will only discuss competitive free-diving as an athletic sport.

Competitive free-diving

Competitive free-diving is currently governed by two world associations: AIDA International and CMAS. Most types of competitive free-diving have in common that it is an individual sport based on the best individual achievement. An exception to this rule is the bi-annual World Championship for Teams, held by AIDA, where the combined score of the team members makes up the team's total points. There are currently nine disciplines used by official governing bodies and a dozen disciplines that are only practiced locally. In this article, the recognized disciplines of AIDA and CMAS will be described. All disciplines can be done by both men and women and, while done outdoors, no differences in the environment between records are recognized any longer. The disciplines of AIDA can be done both in competition and as a record attempt, with the exception of Variable Weight and No limits, which are both only done as record attempts. The following official disciplines are recognized by AIDA, CMAS, or both.

Pool disciplines

  • Static Apnea is timed breath holding and is usually attempted in a pool (AIDA).
  • Dynamic Apnea with fins. This is underwater swimming in a pool for distance. For this discipline the athlete can choose whether to use bi-fins or the monofin (AIDA), (CMAS).
  • Dynamic Apnea without fins. This is underwater swimming in a pool for distance without any swimming aids like fins (AIDA).

Depth disciplines

For all AIDA disciplines, the depth the athlete will attempt is announced before the dive. This is accepted practice for both competitions and record attempts.

  • Constant Weight with fins. The athlete has to dive to the depth following a guide line that he or she is not allowed to actively use during the dive. The ‘constant weight’ ("poids constant") refers to the fact that the athlete is not allowed to drop the weights during the dive. Both bi-fins and mono-fin can be used during this discipline (AIDA).
  • Constant Weight without fins follows the identical rules as Constant Weight with fins, except no swimming aids such as fins are allowed. This discipline is the youngest discipline within competitive free-diving and is recognised by AIDA International since 2003 (AIDA).
  • Free Immersion is the discipline in which the athlete uses the guideline to pull him or herself down to depth and back to the surface. It is known for its ease compared with the Constant Weight disciplines, while the athlete is still not allowed to release weights (AIDA).
  • Variable Weight is a record discipline that uses a weighted sled for descent. Athletes return to the surface by pulling themselves up along a line or swimming while using their fins (AIDA).
  • No Limits is a record discipline that allows the athlete to use any means of breath-hold diving to depth and return to the surface as long as a guideline is used to measure the distance. Most divers use a weighted sled to dive down and use an air-filled bag to return to the surface (AIDA).
  • "The Cube" is also known as "Jump Blue" and is a discipline in which an athlete has to descend to 10 meters and swim as far as possible in a cubic form of 15 x 15 meters (CMAS only).

Each organization has its own rules on recognizing an attempt. These can be found on the website from the respective organizations.

Recreational

Free-diving is also an intriguing recreational sport, celebrated as a relaxing, liberating, and unique experience. Many snorkelers may technically be free-diving if they perform any sort of breath hold diving - it is important to stress the importance of training and supervision when making this association.

Like other water sports, free-diving is associated with therapeutic properties. The experience of freedom in an underwater environment makes free-diving somewhat of a personal and spiritual journey for many. Yoga is used by many practitioners to increase focus, breath, and overall performance. The 'art' of free-diving and the practice outside the athletic and competitive sphere goes beyond the scope of this wiki article.

Physiology of free-diving

The human body has several adaptations under diving conditions[1][2], which stem from the mammalian diving reflex. These adaptations enable the human body to endure depth and lack of oxygen far beyond what would be possible without the reflex.

The adaptations made by the human body while underwater and at high pressure include:[1][2]

  • Bradycardia: Drop in heart pulse rate.
  • Vasoconstriction: Blood vessels shrink. Blood stream directed away from limbs for the benefit of heart, lungs and brain.
  • Splenic contraction: Releasing red blood cells carrying oxygen.
  • Blood shift: Blood plasma fills up blood vessels in the lung and reduces residual volume. Without this adaptation, the human lung would shrink and wrap into its walls, causing permanent damage, at depths greater than 30 meters.

Training

Training for free-diving can take many forms, many of them out of water.

One example is the apnea walk. This consists of a preparation "breathe-up", followed by a short (typically 1 minute) breath hold taken at rest. Without breaking the hold, the participant then initiates a walk for as far as they can, until it becomes necessary to breathe again. Athletes can do close to 400 meters in training this way.

This form of training is good for accustoming muscles to work under anaerobic conditions, and for tolerance to CO2 build-up in the circulation. It is also easy to gauge progress, as increasing distance can be measured.

Before diving, most performance-oriented free-divers hyperventilate to a certain degree, resulting in a lower level of CO2 in their lungs and bloodstream. This postpones the start of stimulation to the breathing centre of the brain, and thus delays the warning signals of running out of air. As the oxygen level of the blood is not increased by hyperventilation, this is very dangerous and may result in drowning. (For more detail refer to the articles shallow water blackout and deep water blackout.) Trained free-divers are well aware of this and will only dive under strict and first aid competent supervision. However this does not, of itself, eliminate the risk of deep or shallow water blackout. All safe free-divers have a 'buddy' who accompanies them, observing from within the water at the surface. Due to the nature of the sport, safety is an integral part of free-diving, requiring participants to be adept in rescue and resuscitation. Without proper training and supervision, free-diving/apnea/breath-hold diving is extremely dangerous.

Education

There are a number of professional free-diving training schools and groups worldwide as well as a growing number of independent instructors. The emphasis of free-diving education tends to be on beginner and intermediate courses, although advanced and instructor programmes are available for those wishing to take their interest further.

The following are a list of free-diving course providers and their prominent teaching locations:

You can also find a list of individual AIDA Instructors via the AIDA Website:

History

The Ama divers of Japan use free-diving for the collection of pearls in a practice that is estimated to date back over 2000 years.[1][3]

The sport is generally acknowledged as the invention of the Bottom Scratchers, a diving club in San Diego, California in the 1930s.[4][5]

Official world records as of July, 2008 (AIDA)

Some famous competitive apnea divers

       

Free-diving in fiction

  • In the Canadian television series Corner Gas, the character Karen Pelly (Tara Spencer-Nairn) competed in static apnea, ranking fifth in Canada with a personal best of over six minutes.
  • The Big Blue starring Rosanna Arquette, Jean Reno, and Jean Marc-Barr is a romance film about two world-class free-divers and is partly based on fact.
  • Into The Blue starring Paul Walker, Jessica Alba, Scott Caan, and Ashley Scott. A group of divers find themselves in deep trouble with a drug lord after they come upon the illicit cargo of a sunken airplane.
  • The Free-diver (2004) Starring Camilla Rutherford, Alki David, Dominique Swain, and Adam Baldwin. A talented free-diver woman is discovered and brought to an island where she is trained by an ambitious scientist to break a free-diving world record currently held by an egocentric American woman.
  • The Greater Meaning of Water (2008) Starring Justin Williford, Mark Brunetti, and Holly London. An independent film about competitive free-diving focusing on the "zen of freediving".[9]
  • In the computer game The Secret of Monkey Island, the main character, Guybrush Threepwood, boasts being able to hold his breath for ten minutes. Although not exactly free-diving, Guybrush ends up underwater in a certain point of the game, and it dies if the player doesn't solve the puzzle in ten minutes.
  • In Greg Iles' novel Blood Memory, the main character Cat Ferry is an odontologist and a free-diver.
  • In the video game Splinter Cell, the opening cutscene shows Sam Fisher, the main character, free-diving in the ocean.

References

  1. ^ a b c Brubakk, A. O. (2003). Bennett and Elliott's physiology and medicine of diving, 5th Rev ed. United States: Saunders Ltd. p. 800. ISBN 0702025712. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  2. ^ a b Lindholm P, Pollock NW, Lundgren CEG (2006). Breath-hold diving. Proceedings of the Undersea and Hyperbaric Medical Society/Divers Alert Network 2006 June 20-21 Workshop. Durham, NC, United States: Divers Alert Network. ISBN 978-1-930536-36-4. Retrieved 2008-04-30.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. ^ Rahn, H. (1965). Physiology of Breath-Hold Diving and the Ama of Japan. United States: National Academy of Sciences - National Research Council. p. 369. ISBN 0309013410. Retrieved 2008-04-25. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  4. ^ Maas T. "AFTER 72 YEARS, THE FAMED SAN DIEGO BOTTOM SCRATCHERS CLUB HAS CLOSED ITS DOORS". BlueWater Free-divers. Retrieved 2008-04-25.
  5. ^ Zieralski E (2003). "Free-dive club of the 1930s was full of underwater innovators". UNION-TRIBUNE. San Diego. Retrieved 2008-04-25.
  6. ^ PAUL MULROONEY and GREER McDONALD. "Free-dive effort truly breathtaking". The Dominion Post. Retrieved 2008-08-11.

See also

Look up freediving in Wiktionary, the free dictionary.
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