Jungle Immersion

Just sit back and imagine…

It is a lovely, sunny day and you are hiking through an abundant jungle on México’s Yucatán Península, creating your very own trail, leading you far away from the hustle and bustle of civilization and up close to the peace and quiet of nature. Suddenly you see some trees wobbling. You pause, observe, and after some seconds spot two beautiful spider monkeys swinging freely from one tree to the next. You delightfully watch them until they disappear and the trees come to a rest.

After a hike of almost two hours, you hear droll “whoop-whoop” sounds – it’s the melody of the glorious Motmot bird and a potential omen that you might be close to discover the object of your desire. And indeed, some footsteps later you arrive at the edge of a magnificent, virgin Cenote (a partially collapsed cave filled where groundwater surfaces) and look down into its crystal-clear, deep-blue water. Surrounding the Cenote you see some imposing trees with their roots hanging down all the way into the water like super-sized, natural straws.

You attach your rope ladder to a massive Ceiba tree and descend about ten meters onto a ledge just slightly above the water surface. Right away you catch a glimpse of some black specks in the water, which upon closer inspection you identify as three-barreled catfish. From your rucksack you unpack: an inflatable buoy, a handy pulley, a long rope with stopper & bottom-plate attached to it and a rusty bottom-weight. Next you assemble them diligently. You fetch your low-volume diving mask as well as your safety belt & lanyard, put them on and with a big leap forward, immerse yourself into the body of water. Your nervous system is first shocked by the cold water, then relieved from the tropical hot air. You pop up with a broad grin and promptly set up the buoy, gently lowering the rope with the bottom weight connected to it.

After you’ve clicked the carbine of your lanyard into the line, you position yourself beside the buoy and recline yourself. You are now comfortably lying on your back, easily floating at the surface, staring into a mix of blue sky, few fluffy white clouds and lush green tree tops. The magnificence of Mother Nature mesmerizes you and you are fully present in this very moment. You gaze at one specific tree branch and let your vision fade out naturally. You scan your body for any tense muscles, releasing one after another consciously and then turn your full attention to your breathing and heartbeat. Your body is completely relaxed and your mind is absolutely calm – you are in a deep, meditation-like state. You initiate your breath control routine (a.k.a. breathe-up technique) to prepare yourself for the dive. When your body, mind and spirit are aligned and you feel 100% ready, you take a deep breath and hold it; you equalize your ears for the first time, turn onto your belly and, with a smooth duck dive, embark on your journey to the underworld: XIBALBÁ

You are descending in a vertical position strictly along the line. The alternating arm and leg strokes are only interrupted by a frequent pinch of your nose to equalize your ears again. Five meters, ten meters… you feel gravity slowly but steadily grabbing you …fifteen meters… you can gradually ease off your movements …twenty meters… you cease all movements and commence the freefall …twenty-five meters…you fully enjoy the effortless “flight” down the water column …twenty-nine meters… slightly ahead of the stop-ball you grasp the rope with both hands, turn around and let yourself hang. You hear… nothing …absolute tranquility. Cautiously you inspect every direction and marvel at this mystical underwater scenery. On the hilly floor below, and illuminated by a splendid beam of light, are some fragments of Mayan pottery. In front of you is a cavern area with enormous stalactites. Fossils of corals and conches are embedded in the karst wall behind you. And upwards, far away and yet seemingly so close, there is the picturesque version of the upper world.

It feels like life stands still, but you sense that it is time to depart on your return trip. You make one initial pull on the line and set yourself in motion. Like on autopilot, the arm and leg strokes are repeating …twenty-five meters, twenty meters, fifteen meters… with buoyancy increasing every meter, you can consistently ease up your movements…ten meters… suddenly another human being appears. It is your buddy, who was there the entire period, meticulously supervising you from the surface and now accompanying you on the last third of your ascend. She winks at you to welcome you back to reality and you smile at her in a mix of comfort, gratitude and satisfaction. Five meters… at this point no more movements are necessary as positive buoyancy takes over and brings you up towards the surface. You and your buddy simultaneously surface, both firmly gripping the buoy and immediately executing recovery breaths. Now the only things left to complete this fabulous dive are; to take off your mask, give your buddy a distinct OK signal and tell her with a clear voice “I am okay”.

How did you like this fictive, “textual” experience? Leave us your comment or send us a message!

Did you know that Avatar 2 will feature the most extensive freedive footage ever shot?

... and is already considered the most momentous dive movie ever made?

The Avatar saga will evolve into five chapters and is James Cameron’s personal story with the distinctive message to not sacrifice everything for pure greed and conquest. It might take all five movies to really make that message loud and clear for the whole world. James Cameron is a free- and scuba diving explorer at heart and he wants to share his inspiring vision of the underwater world in Avatar II. The movie is said to last about three hours and currently only the following is known about the plot: 12 years after exploring Pandora and joining the Na'vi, Jake Sully has formed a family with Neytiri as they are wandering across the expansive world of Pandora, meeting new allies in the form of the water-dwelling Metkayina clan led by Tonowari. Everything changes when the R.D.A. (Resources Development Administration) once again invade Pandora to finish what they’ve started.

Many of the actors doing a lot of underwater work themselves, a substantial part of that involves freediving, which many of the crew including stars Kate Winslet and Sigourney Weaver had been trained in by Kirk Krack, a world-renowned expert in freediving. The cast, among a seven-year-old child, are up to four minute breath-holds. He himself spent two years working on the film as a freedive safety, training and educational consultant. Most other movies with underwater scenes are using the “dry-for-wet” method, where the scenes are shot in the dry and the water is only simulated by technical manipulation, quite to the contrary of Avatar II where all scenes are “wet-for-wet” shots, hence real performance capture underwater. It is said that the crew logged over 200’000 freedives between the cast, safety, camera people, grips, special effects technicians. On principal cast days some crew members spent about 12 hours in the water tank. Apparently, two of them logged 3 ½ hours of breath-holding on one busy day.

Even though the principal photography has been wrapped by the end of 2019, the movie will not be released until 17th December 2021, due to the extremely complex post production.

That gives you plenty of time to dive into the magical, somewhat AVATAR-like cenotes of the Yucatán peninsula in Mexico.

Are we made to be under water?

Sadly not anymore. Although all life originated from water, we've gradually lost many of our biological ties with it. But there is still one astounding evolutionary adaptation slumbering in all of us: The mammalian diving response or dive reflex We share it with whales, dolphins, seals, penguins and the likes. While they need it to function in their everyday life, it is designed as a survival mechanism to us. However, we do not benefit from its effects merely in an emergency, but as well when diving on breath hold = freediving a.k.a. apnea.

Initial stimulus

Facial immersion in water or even just facial contact with water; the colder, the faster the reaction. The receptors in the face, especially on the forehead and around the nose, are connected to the trigeminal nerve. Said nerve transmits the information to the brain, which stimulates the vagus nerve. This results in the immediate closure of the airway as well as a number of physiological changes to optimize the body’s oxygen management towards conservation.

Additional stimuli: Breath hold, pressure increase Responses 1. Laryngospasm - only in infants up to 6 months: The vocal cords are immediately closing, thereby constricting the windpipe and thus inhibiting water from entering the lungs => prevent drowning. 2. Bradycardia - slowing of heart: The heart is one of the strongest muscles in our body and every heartbeat consumes oxygen. During breath hold our body will naturally slow down the heartbeat by 10-30% (in trained freedivers up to 50%+) to conserve oxygen and consequently extend our time under water. 3. Vasoconstriction - constriction of blood vessels: When our blood vessels constrict, blood flow to our extremities is reduced, thus increasing the concentration of oxygen-rich blood towards our vital organs (lungs, heart and brain). 4. Blood Shift - As a result of the vasoconstriction, blood is shifting from the extremities into the vital organs and chest cavity. The alveoli and capillaries in our lungs become engorged with oxygen-rich blood (= incompressible), which replaces the air space (= compressible) in our lungs. The blood acts as a cushion, preventing our lungs from collapsing when dving deeper than our residual lung volume (~35m+). Blood shift also occurs in the other organs of the body in a similar manner and with the same result. 5. Spleen Contraction - The spleen, an organ that stores red blood cells, contracts up to 20%, thereby releasing red blood cells into our circulatory system. This means that more oxygen can be stored in our blood. Furthermore, the additional blood cells allow the body to resume its normal balance faster after a prolonged breath hold. Life Hack

Calm down your nerves at any time by enabling the mammalian diving response. Simply put a cold wet towel on your face; make sure to cover the forehead and the nose. Because the dive reflex excites the vagus nerve, your heart rate drops and your body starts relaxing. To reinforce relaxation, breathe slowly and deeply in a ratio of 1:2, e.g. inhale for 10sec, exhale for 20sec, if you like you can also add a short pause (= breath hold) after the inhalation.