Freediving
When apnea diving or free diving the diver inhales before the dive and used as opposed to scuba dive for his only this one breath. The period of holding one's breath is called apnea [ Apno ː ə ] ( from Greek ἄπνοια ápnoia non- breathing, πνοή pnoe breathing, breath ).
Freediving is the oldest and most primitive form of diving. As early as the Stone Age apnea divers have collected, for example, shells, sponges and pearls and hunted fish with spears. Nowadays freediving is operated as a leisure activity and as a scuba diving to extreme sports. In the leisure sector, it is all about exploring the underwater world and to the general conditioning for scuba diving. In competitive sports, however, always longer apnea times or distances and low benefits are sought through targeted training. The world's largest distribution has Freediving in the form of underwater fishing.
Physiological basis and dangers
Breathing is usually an involuntary process, which can also be controlled consciously but. The respiratory stimulus is essentially doing triggered by the rising carbon dioxide content of the blood. Without exercise, it is hardly possible to suppress the respiratory stimulus over an extended period of time. For specific training dive duration, however, is limited mainly by the oxygen content of the blood. If its partial pressure under an individual limit, the diver is unconscious.
Conscious breathing or hyperventilation before diving does not lead to an increase in the oxygen supply, but a lowering of the carbon dioxide content in the blood. Depending on the duration and intensity of Voratmung they will lead to a delayed respiratory irritant. It may be that only begin after falling below the required oxygen content. Especially the novice is not able to recognize the signs of the ensuing risk fainting. They coat the affected usually sudden and without warning. If the person concerned is not brought within a short time on the water surface, accidents or drowning may be the result (pool - blackout). Therefore, the protection of the diver plays a particularly important role. Immersed is at least two people saved is usually mutually; in this way, accidents are very unlikely. The accident rate during breath-hold diving is therefore - except deep sea diving with variable weight or diving under ice - very low.
During deep diving under apnea are due to complex physical and physiological relationships more challenges to a free diver added. In addition to a more economic approach to oxygen consumption especially the ability to equalize pressure is important. As the diver must return to the surface in any case, he has in a deep dive hardly ways to end a trial early. Therefore, the diver makes the decision about the maximum depth before the dive. In competitive sports, the length of the guide rope is adjusted precisely to the targeted depth. A safety line (also: " Lanyard " ) connects the diver with this guide rope.
In the depth of the ambient pressure amounted to 10 m increases by about 1 bar. This increase in pressure acts on all air-filled body cavities. With increasing depth, but also act changes the gas partial pressures on the physiological and neurological processes in the body ( low noise and the like. ). The pressure difference is noticeable mainly by a sharp pain in the ear. The eardrum reacts very sensitive to pain and would tear without pressure compensation after a few meters. Other painful on sensitive body cavities are the frontal and maxillary sinuses. The diver should the air pressure in these body cavities therefore often align against the external pressure. To this end, he repeatedly pressed air from his lungs into the cavities. The lung itself, however, is already compressed in depth about 25 to 35 m on the volume at maximum exhalation.
To dive deeper still without injuries, the diver must adjust his body and learn complicated balancing techniques. Through specific exercises are used, among other things, the elasticity of the chest, the diaphragm and the intercostal muscles improve. In addition, but also develops the ability of the lung to the increasing pressure by accumulation of blood and lymph fluid in the tissues adapt. This process, which is called "Blood Shift" is used by many diving mammals such as seals and whales.
However, the adjustment processes do not take place at every diver to the same extent and at the same pace. Exaggerated ambition, but also the change in perception by the low noise, the physical warning signals overlap so strongly that the diver exceeds its physiological limit. It can then lead to micro- injury and edema in the lungs, throat, jaw and sinuses. To minimize the risk of injury, increase the depth of each dive Apnoisten in very small steps.
In a controlled descent the risk of barotrauma freediving is also low. To ensure the pressure balance in the sinuses and middle ear, but should not be used for colds and inflammation on the diving.
Dekompressionsprobleme are freediving at grassroots level ranges up to about 30 m unlikely, since the dwell time and immersion depth is not sufficient for saturation of the tissue. In deep diving with a constant weight of DCI are not yet known, but theoretically possible. It is believed that it has come in pearl divers who take many deep dives within a short time Dekompressionsproblemen. In the area of no-limit diving decompression illness are viewed as a threat. For combinations of scuba and free diving ( eg free dives in the break between scuba diving ) has been reported several times from decompression sickness.
Training Methodology
The beginner learns in training the first conscious breathing and the relaxed approach with his breath charm. In addition, a general conditioning is done by swimming, running, etc., and a special technique training for swimming under water. In advanced training, he learned under the watchful eye of his training partner signs of incipient oxygen deficiency and thus to recognize his own limitations. This approach has buttons at the same time a large effect adjustment. The diver turns physiologically and mentally one to this extraordinary burden. He can relax, the diving reflex intensifies and heart rate decreases. Thus, by regular and conscious exercising thereby the oxygen consumption significantly decreased and the apnea power to increase substantially.
Experienced Apnoisten can be controlled to get very close to the limit and even exceed this target. Border crossings are avoided, however, wanted as they act by reducing power. Blackouts are very rare. However, changing conditions such as competitions place increased demands on the Leistungsapnoisten. In order to prevent border crossings yet, is immediately provided assistance in visible, self-endangering loss of control or even fainting in the competition and secured the athlete. The participant will be disqualified and his performance was not rated.
Leistungsapnoisten put a modified training methods from the competitive sports such as hypertrophy, interval, and lactate tolerance training, especially for the improvement of their dynamic and deep diving services. The few so far carried out measurements of vital signs experienced freedivers are far outside the normal limits for healthy non-divers. So resting heart rate values were below 24 beats / min. Heart rate, hemoglobin values in excess of 16 g / dl, lactate levels of over 28 mg / dL, and lung volume of about 10 liters ( vital capacity ) determined.
Equipment
The equipment of a free diver ranging from a bathing suit to the complicated slide stainless steel construction. The beginner can use a simple ABC - diving equipment and a normal wetsuit. For advanced users, there are specially adapted to the requirements of equipment:
The suit is then made particularly flexible neoprene with a good fit. Most here a suit is from so-called " open cell neoprene " is used because this is characterized by a better heat insulation. The flippers have a particularly long and hard leaves, in competition specific mono fins are often used. The diving mask for deep diving has a very small internal volume, but normal swimming or chlorine glasses and usually a nose clip can be used in hall or pool.
More freediving utensils are the elastic weight belt, a neck lead to reach the apnea neutral buoyancy, which is usually wound on a cylindrical buoy guide rope, and a stopwatch and a depth gauge.
Freediving as a competitive sport
Basics
Freediving is also applied as a competitive sport and competitive sport. For these competitions and record attempts, there is a generally accepted rules of the Association of freedivers Aida. This extensive regulatory framework prescribes mandatory safety standards as well as the conditions for the recognition of the achievements and records.
The most important rule is that the athlete must realize his performance with full consciousness and without assistance. If he loses consciousness or he needs for his safety outside help, he will be disqualified and his performance was not rated. The performance ends after the respiratory openings have left the water and in the rules of well- written protocol was fulfilled.
Competition or record disciplines
When apnea competitive sports, a distinction between the pool and deep diving disciplines:
Pool disciplines
In all disciplines, jumping off the edge of the pool is not permitted.
Deep diving disciplines with constant weight
With just one breath, the diver tried it as deep as possible and again to dive back to the surface. The diver must carry weights (lead ) to overcome its own buoyancy, but has all the weight he used to descend, even from their own resources to the surface ( therefore " Constant" ) position. Is evaluated the depth in meters.
Deep diving disciplines with variable weight
Here the diver attempts with one breath to dive as deep as possible and then come back to the surface. The diver can (usually a run on a rope slide design ) draw by a weight or a driven element in the depth and leaves it back there.
These disciplines are no competition disciplines because of the incalculable risks. The ratification by the Association of Free Divers ( AIDA) is located in a controversial discussion.
Official World Records ( AIDA )
AIDA International is the largest recognized association for the competitive freediving. This organization ratified among others, the globally recognized World Records: The organization CMAS has partially own disciplines and regulations.
Dive
Fins
Fins
Weight
Fins
Fins
Immersion
Weight
Fins
Limit
(As 7,791,122,825,026th March 2013 )
Manipulations and doping
Are presently being discussed controversially for possible manipulations and the suspicion of doping among athletes some services. The current regulations are not sufficient to exclude unsportsmanlike conduct this type.