For some of us, the thought of descending hundreds of feet toward the seafloor on just a single breath brings to mind nothing but the most primal of terrors. But for others freediving is a sport, a way of life and a way to commune with nature. Freediving, or underwater diving without breathing apparatus, sees humans enter the most inhospitable of environments and experience life on this planet as very few others do.
10. People Have Been Freediving for Thousands of Years
It’s estimated that freediving has been practiced around the world for millennia. The earliest evidence we have dates back at least 7,000 years to the Ertebølle culture of Denmark and Sweden. These divers would plunge into the sea and harvest the seafloor for shellfish. Ancient Persians would risk life and limb to bring precious pearls to the surface. The Romans had special freediving military units, Urniatores, who would be tasked with retrieving items from the seafloor andsabotaging enemy ships. The ama, female freedivers from Japan, have been gathering pearls, seaweed and all manner of food for more than 2,000 years. Their tradition continues to this day, with ama sometimes completing more than 50 dives in a day.
9. Modern Freediving Started With a Bet
In the second half of the twentieth century, interest in freediving grew thanks to the exploits of two men. In 1913, the Italian ship La Regina Margherita lost an anchor off the Greek coast and a reward was offered for its retrieval. A local sponge diver, Haggi Statti, descended between 249 and 288 feet to recover the anchor and was handsomely rewarded. This depth was considered by many to be far too deep to survive, and the story was thought to be apocryphal. It wasn’t until 2001 that the Italian navy officially confirmed the reports to be true.
The reason for so much skepticism was that freediving had fallen away from everyday consciousness. Commercial fishing and the development of diving technology had pushed freediving to the fringes. Modern science surmised that divers would surely perish at such depths. Boyle’s Law, for instance, predicted that a diver’s lungs would be crushed by pressure in water that deep. In 1949 Raimondo Bucher, a lieutenant in the Italian Air Force, dove down 30 meters in the Gulf of Naples, winning a 50,000 lira bet. Luckily, his dive took place in front of several officials who could verify it as legitimate. This kick-started renewed interest in freediving and the modern sport was born soon after.
8. It’s Now An International Sport
Buchner’s achievement was soon to be surpassed as the modern sport of freediving took off. The International Association for Development of Apnea (AIDA) is the body that maintains records and regulates the rules in the various disciplines of apnea, or breath holding. Apnea covers static breath holding as well as freediving, so some events take place in a pool.
Most disciplines, however, take place in the sea, where divers must compete to reach the deepest point they can before returning to the surface safely. Divers submit a target depth before the competition starts. A diving rope allows officials to set the target depth. They then attempt to reach that depth with a single breath. If they successfully reach it, they must retrieve a marker from a weight attached to the line and return it to the surface. How they do that depends on the particular discipline. The most challenging, and seen by many as the purest form of freediving, is constant weight no fins (CNF). In CNF, the diver must maintain the same weight (they can’t release any weights they may have used to aid their descent) and they can’t use fins to propel themselves. Having reached their target depth, they can only touch the rope once to turn around and begin their ascent. Today’s world record for CNF is an astonishing 331 feet (101 meters) and is held by New Zealander William Trubridge.
7. There’s Great Variety in the Disciplines
There are a variety of disciplines in which freedivers can compete, and each has its own world record for both male and female competitors. Perhaps the most remarkable records come from two very different types of apnea. In static apnea, divers compete in a pool and remain still throughout their attempt. The goal is to hold one’s breath for as long as possible. The current men’s world record holder is Branko Petrovic, who held his breath for a remarkable 11 minutes and 54 seconds. A variation of natural static apnea allows competitors to breathe pure oxygen for up to 30 minutes before their attempt, which boosts the body’s oxygen stores. In this discipline, Goran Colak holds the world record with a mind-boggling 23 minutes!
At the other of the scale in terms of movement is no-limits apnea. These competitions take place at sea and allow competitors to use any means they like to reach their desired depth. Divers use weighted sleds which drag them downward and balloons of air to help them ascend. This discipline is incredibly dangerous, as divers reach depths that would normally be out of reach. Austrian Herbert Nitsch is known as the deepest man on Earth, holding 33 world records in various disciplines. In 2007 he set a new record for no-limits apnea, by descending 702 feet (214 meters) before safely returning to the surface. That’s the equivalent of descending 65 floors and back again on only one breath.
6. Freediving Is Helping Scientists
Freediving is employed in scientific research and wildlife photography. Diving with scuba gear produces noise and bubbles that act as a disturbance to nearby animals. Freediving eliminates this noise and allows divers to enter the ocean as silently as another animal. Animals behave much differently when the technological barrier is removed and they’re approached on their terms. The comfort the animals feel has led to stunning photography and scientific advances in poorly understanding areas, including whale vocalization and socialization. Freediving has also allowed scientists to tag devil rays and track their migrations, giving new insight into their behavior. Divers have even been welcomed into sperm whale pods.
5. It Exploits A Reflex We All Possess
Freediving to great depths is possible due to a mammalian diving reflex all mammals possess to varying degrees. There are several remarkable changes that occur when the reflex is initiated. Bradycardia, the slowing of your heart rate, can begin as soon as cold water touches your face. A human’s heart rate can be reduced by up to 25%. The lowest recorded heart rate for a freediver was 14 beats per minute, or a third less than the average heart rate of a patient in a coma. Splashing cold water on your face when you’re feeling unwell or flustered induces this change.
A decreased heart rate reduces the need for bloodstream oxygen, which can then be used elsewhere. Peripheral vasoconstriction closes off the capillaries in your extremities so that more blood is directed to your heart and brain. Our muscles store about 25% of our oxygen so they can keep working after the fresh supply is cut off. Blood shift, which only occurs during the deepest of dives, allows the organ and circulatory walls to become engorged with blood which protects them by maintaining a constant pressure.
4. A Diver’s Buoyancy Will Reverse as They Descend
If you were bobbing around near the surface or sea, you would experience positive buoyancy because our bodies are less dense than the water surrounding us. But descend far enough and your body will become denser as the pressure around you increases and compresses your body. Between 25-40 feet down you’ll come to a point of neutral buoyancy where you’ll no longer feel like you’re being pushed up to the surface. Cross this invisible barrier and you’ll become negatively buoyant and start to sink. This allows competitive freedivers to glide down to their desired competition depths, and for fishermen and pearl divers to walk along the sea bed. At these depths, negative buoyancy can make walking on the seabed feel similar to walking on the moon. This video of Guillaume Néry is a wonderful illustration of how a diver’s buoyancy will reverse in deeper water.
3. It’s the Second Most Dangerous Sport in the World
It’s estimated that only BASE jumping claims more lives than freediving. Although only one diver,Nicholas Mevoli, has died while taking part in an organized competition, many lives have been lost in training, recreational diving and fishing. It’s estimated that of the 10,000 active freedivers in the United States, 20 will die each year. This works out to one death in 500 divers. That’s comparable to one in 60 for BASE jumping and one in 1,000,000 for mountain climbing.
2. Freedivers Don’t Get the Bends
Despite being able to reach depths far greater than scuba divers, freedivers generally don’t run the risk of getting decompression sickness. This terrible affliction occurs when scuba divers fail to decompress adequately before returning to the surface. Nitrogen bubbles form in the tissue, joints and bloodstream. This is due to breathing compressed air at different depths and pressures. The symptoms of decompression sickness range from joint pain to death, with a lot of other horrible effects in-between.
Freedivers don’t get this because they take only one breath at the surface, at ambient pressure, and spend only a few minutes underwater. Their lungs are compressed as they descend but expand again as they come up. There isn’t enough nitrogen in this single breath to bubble into the blood, and it’s removed as soon as the diver surfaces.
There are, however, rare exceptions to this. Freedivers who are diving multiple times a day, like fishermen, can experience decompression sickness due to their total time under water and pressure. And no-limits freedivers run the risk of getting the bends as they use sleds to take them to their desired depths. These weighted contraptions drag them down more than twice as deep twice as quickly as other divers. They also use balloons to quickly ascend. This can be too fast for the body to expel the nitrogen.
1. Aquatic Breath Holding Made Brief Appearances in the Olympics
Due to the inherent dangers and logistical challenges, it’s thought that freediving won’t make an appearance at the Olympics anytime soon. However, in the past there were two bizarre flirtationswith apnea and diving. At the 1900 Paris Olympics, medals were awarded for underwater swimming. Frenchman Charles Devendeville swam 60 meters underwater in a time of one minute and eight seconds to take the gold. At the 1904 St. Louis Olympics, American William Dickey claimed gold in the plunge-for-distance event. This required competitors to dive as far as they could into the water and then remain motionless as their momentum propelled them forward. Their distance would be measured after 60 seconds or as soon as their heads broke the surface. He won with 19.05 meters.
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