Remember when you were a little kid in the bathtub and you tried to hold your breath as long as you could? You were freediving! Freediving is like scuba-diving, minus one important piece of equipment—a breathing apparatus. In this sport, divers take deep, long breaths of air and see how far or how deep they can swim. Some freediving events take place in a pool or where there is a large body of water. However, most of these competitions are held in the Mediterranean or Caribbean where the water is warm, deep, and yet amazingly clear. Freedivers compete in several disciplines:
No Limit or NLT: Divers use a large weight to take them down several hundred meters and use a balloon to ascend. This technique allows competitors to go incredibly deep quite quickly. It is the ultimate depth competition.
Variable Weight or VWT: Divers descend using a ballast weight like in NLT diving, however, they ascend by pulling on a line attached to the boat above them.
Constant Weight or CWT: A diver uses nothing except his fins and body to propel himself down to a predetermined depth and then to ascend without touching the line.
Constant Weight Without Fins or CWF: Divers use only their body—no fins—to propel themselves downwards and back up to the surface. This is by far the hardest discipline since it is the most demanding on muscles, is the slowest, and requires the most finesse.
Free Immersion or FIM: A diver uses the line to pull himself through the water.
Dynamic With Fins or DYN: Divers compete for distance—not depth—using fins
Dynamic Without Fins or DNF:Same as above, except without fins.
Static Apnea: This is the classic breath hold. Divers compete to see who can hold their breath the longest—usually this is done in a pool with the diver drifting on the surface.
Freedivers can descend to up to 244 meters—702 ft.—on a single breath. This record is held by Australian born Herbert Nitsch. How do these amazing athletes do this? The freediving technique is incredibly complex, and it takes years to fully understand it. Divers can undergo pressures of up to 3 atmospheres. At these depths, all the air that freedivers hold in their lungs and spleen—yes, they hold air in their spleens—can be compressed to a quarter of the volume and the lungs are likewise compressed to the size of a pear. An additional danger is nitrogen narcosis. Nitrogen breaks up in the lungs and bubbles up in the blood—leading to blackouts, dizziness, and confusion—all terrible side effects for a human many feet underwater. Freedivers must be highly aware of how much air they inhale and hold during a dive. Most freedivers breathe normally until they are about to begin their descent. Then, they take from one to four deep breaths through their diaphragm to max out their lung capacity. Obviously, the more oxygen in your lungs, the longer your body can sustain itself without breathing. Another problem for freedivers is equalization. Whenever you swim to the bottom of your pool, your ears feel pressure. To equalize the pressure, you pinch your nose and blow. This is what all freedivers do. As you descend the amount of air in your ears, your sinuses are compressed. You must blow more air into those cavities to match the pressure of the water around you. If a diver does not equalize often enough, he may burst an eardrum or pop a blood vessel in his sinus. This is incredibly painful and can often end a career.
In order to experience a similar sensation to a freediver, here is a fun exercise you can do.
Take a normal breath and, exhale. Then hold your breath. How long did you last? Twenty seconds? Now try this. Sit with good posture with your shoulders back and your chin level with the horizon. Breath normally for 30 seconds and then take 3 deep breaths from your belly—not your chest. Then time how long you can hold your breath. There will be a noticeable difference.
Even the best freedivers in the world do this. You may have noticed something odd. As you approached you max breath hold, you belly may have felt incredibly uncomfortable. Normally, after these “contractions”, you gasp for air. If you have enough control of your body, however—particularly its involuntary reflexes—that is, your urge to breathe—you may have felt your body try to take a breath without you opening your mouth. This is a very important part of freediving. Freedivers must have incredible body and mind control. They need to stay calm and peaceful to keep their heart-rates low and ignore the overwhelming urge to breathe. The lower your heart rate, the less oxygen is spent. Also, freedivers must push their bodies to keep functioning—while staying calm—without normal amounts of oxygen. Clearly it is an incredibly demanding sport. However, our bodies also have some interesting aspects that freedivers can use to their advantage. Something all mammals have is the mammalian dive reflex. When our faces touch cooler water, this reflex is triggered. It lowers our heart rates and draws the blood from our extremities—fingers and toes—to our vital organs. This is called the blood shift. Blood flows into the lungs, and other organs to help them withstand the intense pressure.
Despite its many dangers and difficulties, freediving is growing in popularity. Being upside down 12 feet below the surface watching the water is an incredible feeling which is highly addictive. Freedivers compare that state to flying. The benefits of freediving are a healthier heart, larger lung capacity, better mind and body control, better oxygen efficiency, and more freedom underwater.
Boyd, Lou. “Competitive Freediving: Freediving Disciplines And Records.” mpora.com, 13 Nov. 2015, mpora.com/diving/competitive-freediving-freediving-disciplines-and-records#AfxdARCH3yd7FChJ.97. Accessed 17 May 2018.
Farrell, Emma. “Effects of Pressure and Depth.” deeperblue.com, www.deeperblue.com/
effects-of-pressure-and-depth/. Accessed 17 May 2018.
Severinsen, Stig. “The Diving Reflex.” breatheology.com, www.breatheology.com/
mammalian-dive-response/. Accessed 17 May 2018.