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Listen Up: Freediving is About to Enter a New Era if Oxama has a Say!

Now, just like their triathlete counterparts, freedivers will be able to access their realtime biometric performance data, including heart rate and blood-oxygen saturation, enabling them to fine-tune their performance, thanks to an Italian start-up called Oxama. What’s more, the device, which links to your smartphone, uses an innovative audio interface, enabling divers to geek out on their metrics, hands-free. Fortunately, adventure writer and photographer Florine Quirion caught up with the Oxama team. Here’s what they had to say.



by Florine Quirion. Header image by Lorenzo Mittiga. Photos and video courtesy of Oxama.

The current tech craze inspires rapid hardware development in many industries, including recreational scuba and tech diving. However, tech innovators have seemed to skip over freediving—until now. In mid 2022, Oxama will introduce an audio freediving computer. 

In 2019, Claudio Mattavelli, Massimo Moi, and Vincenzo Palumbo founded Oxama, an Italian start-up. The three passionate freedivers from Milan define their computer as a virtual vocal coach that “tracks your freediving experience.” The team took naming inspiration from blood oxygen saturation (Ox) and the name of pearl divers in Japan (Ama).* They ran a Kickstarter campaign at the end of 2021, gathering 60% more than their initial objective of €15,000. 

We met virtually with Massimo, Oxama’s COO, for an exclusive interview following their successful campaign. Let’s dive into how Oxama is going to change the freediving world.

*A quick check with Urban Dictionary paints another picture. Oh those Italians!

Massimo, tell us a bit about yourself… you have been freediving for decades; how did you start, and how has your diving changed over time?

I started freediving at a young age with my dad in Italy in the 1980s. In the Mediterranean Sea, spearfishing is a common tradition, and we used to spend summer vacations spearfishing for hours in the waters of Liguria and Sardinia. We had so much fun that we often lost track of time, even though.  At that time, all we had was one mask and two fins. 

Later, in the 2010s, I started formal freediving training in a pool. I met Claudio [Mattavelli] and Vincenzo [Palumbo] in 2016 while I was training. The first freediving wrist computers had appeared only a couple of years before, and only recently did  that technology get involved in freediving. But despite a handful of brands releasing specialised freediving computers, none of them ever considered biometric data.

How did you come up with the idea for the Oxama freediving computer?

I didn’t have a dramatic wake-up call underwater, but I began to feel a profound desire to improve underwater safety. At the beginning of 2017, Claudio, Vincenzo, and I were preparing for our next summer trip. During our pool training, we realised there should be a way to improve our underwater preparation. 

We searched for new exercises that would extend our physical abilities underwater, which led us to conclude that we needed to track how our bodies reacted to these exercises to optimise our results, and the initial idea for Oxama was born. We wanted to better understand the link between our physiological parameters and how long and how deep we could stay underwater. We officially started the Oxama project in 2019. Today, our first version can track eight parameters: heart rate, blood oxygen saturation, head angle, speed, acceleration, depth, and time.

Freedivers wear the Oxama computer on their face—below their mask—allowing them to hear their parameters. Could you explain a bit more about how it works?

Data analysis of a deep dive at Y-40 (see details below)

Before the dive, the diver, relaxed, has an heart rate (HR) around 60bpm but during the ventilation it rises up to 90bpm due to the intense respiratory effort. The dive begins and, with a constant speed of -1.3m/s and an almost perfect vertical head posture of -83 degreee, the diver reaches the bottom of the pool at -42m. The HR drops down and, after a static rest of 60 seconds, it reaches the minimum of 52bpm due to the diving reflex. The blood oxygen saturation (Spo2) remained between 97 and 99 % during all the descent, and it starts to decrease when the ascent begins. During the ascent, the speed is about 1.0 m/s, the head posture between 70 and 90 degrees, the HR increases up to 100bpm at the surface. The SpO2 decreases during all the ascent and touches its minimum of 85% as the breath holding end, then quickly increases up to 90% in few seconds as the ventilation starts. In next 30 second, the divers recovers and HR comes back to the basal value of 70bpm and the SpO2 to 99%

The idea is based on bone conduction, which carries sound vibrations through the bones of the skull and inner ear. With audio-based information instead of text on a monitor, freedivers can access their underwater performance stats without having to look at their wrists. The computer includes a bone transducer encased in a soft silicone mask. Using bone conduction instead of earphones, the transducer generates a human voice and communicates the audio via sound vibrations that travel through the skull and inner ear, which the eardrums perceive as audible sounds.

Vincenzo came up with the high-tech idea. We are lucky to have an experienced optic quantum physicist on our team! He started experimenting with simple pulse oximeters found in pharmacies. Then, he had this breakthrough idea to avoid interrupting  freedivers’ concentration. 

Divers, without the need to read a computer on their wrists, can maintain the best dive position at all times. Freedivers can keep their bodies streamlined without losing focus on their sensations. 

Can beginners and competitive freedivers use the Oxama computer differently?

All freedivers (beginners or athletes) can set Oxama to different modes. They can choose the parameters and the exact moment when to listen to the recorded values. The Oxama computer currently has four audio modes: quiet, alert, chatty, and mute.

As a virtual coach, Oxama can help beginners better understand their own physical limits. This is when the blood oxygen saturation information is most helpful. The Oxama computer gives the beginner the information they need to start freediving safely in a controlled manner.

In the case of competitive divers, some of the most valuable parameters are the ascending and descending speed and the head angle. With these parameters, divers can improve their performance by pinpointing their own improvement benchmarks.

Could you give us more details about how Oxama measures  blood oxygen saturation and heart rate?

With Oxama situated on the freediver’s face, the computer has close access to facial blood vessels. Our patented technology exploits the optical properties of blood flow to determine blood oxygen saturation and heart rate. The facial artery’s lateral nasal branch—on the side of the nose—is an excellent point of measure. Like a pulse oximeter measures oxygen saturation and heart rate from the blood vessels of the fingertips, Oxama can do the same on the face.

However, there is another benefit to taking measurements on this part of the body. As freedivers descend deeper, their blood moves from their peripheral limbs towards the inner body, and vasoconstriction occurring at deep depth makes precise measurements at the finger or wrist extremely difficult. Hence, the face is an excellent location to measure the blood metrics no matter the depth.

Since divers can access all of Oxama’s data on their smartphones, what are your tips for interpreting the data to extend dive time? Have you found any interesting observations so far?

With data graphs, freedivers can understand how and where to improve their dive time. The blood oxygen saturation and heart rate data are significant indicators—they show divers where they need to improve both concentration and relaxation to reduce their physical strain. Physical effort saps the limited supply of oxygen divers took at the surface. Oxama also uses it to recommend a recovery time between dives. This is a fantastic way to track their general fitness development over time, as well.

During the first phase of testing, our team noticed that their oxygen saturation remained constant for the entire  descent period and decreased during ascent in the final meters. In the same way, their heart rates remained constant throughout the descent and then began to increase during the ascent.

Another interesting observation was the impact of the head angle in ascent and descent—the more aligned with the rest of the body, the better. By not requiring divers to look at a computer on their wrists, Oxama helps them maintain optimal alignment. The same applies to descent and ascent speed which need to be as consistent as possible to maintain energy efficiency. 

When will free divers be able to try Oxama computers in 2022?

Our goal is to launch the Oxama freediving computer in July 2022, when, hopefully, freedivers will be able to buy it from our website. We are also currently negotiating retailing deals with dive shops in Italy before expanding globally.

To that aim, we have started organising test sessions in diving pools. In mid-February, we will do a session at the Y-40 deep pool in Padova, Italy, with its technical director, Marco Madollo. We want to repeat the test in March 2022 with free diving athletes.

Additional Resources

InDepth: The Making of the Biometric Diver: DAN Europe’s Alessandro Marroni is Realising a 50-year old Dream

To explore additional stories, videos and webinars on freediving click: FREE

Florine Quirion is a writer, underwater photographer, and dive travel blogger at World Adventure Divers. She dives in tropical to extreme cold waters and selects destinations where adventurous diving and cultural discoveries are a part of the journey.


Close Calls: I Ripped My Drysuit a Kilometer Back In The Cave

It’s a potentially life-threatening equipment failure that most divers have thought but, but outside of minor leaks, few have experienced, and almost none have trained for. It certainly got the attention of photographer Fan Ping as he felt the chilly Florida spring water rush into his suit. Here’s how he survived the dive.




By Fan Ping

🎶🎶 Pre-dive Clicklist: 平凡之路 (The Ordinary Road) by Pu Shu

Finally I had to say goodbye to my six-year old drysuit, in an unexpected way.

It was a cloudy day in January. There were not many people at Ginnie Springs in Florida as the temperature there was still too cold for the inflatable unicorns and flamingos with their masters in swimsuits that you see so often at the park. My friend Derek Dunlop and I met at the parking lot in front of Devil’s underwater cave system, and we started preparing for our photo shoot in Berman’s Room, at about 1006 m/3400 ft on the main line.

I sidemount my camera to the right.

As usual, we had first talked about the shooting plan with a storyboard and had decided to go in with six video lights since Berman’s Room is pretty big and fairly tall. Then we started preparing our rebreathers, but things did not go smoothly. Derek had a leak in his DSV, and then one of his O2 sensors stopped working for an unknown reason. Fortunately, he managed to fix both problems, but by then it was almost 2 pm already. I am a firm believer of ‘Rule of Three’ (If you have three major problems before you start the dive, then you should quit for the day), but I am also a photographer who was eager to capture the last piece of my Ginnie Springs project.

Berman’s Room
The Henkel

We got on our scooters and started diving. When I have many lights, I usually put two on the camera, which is side mounted on my right like a tank, two in my left thigh pocket, and the rest on my buddy. We dropped our own sidemount bailout tanks at Stage Bottle Rock at 1800’ and arrived at our destination 45 minutes into the dive as planned. We spent about 60 minutes playing with the lights and shooting, and then turned the dive happily at 105 minutes.

I was leading on the way out, riding in the high flow and thinking about the photos. When I passed the restricted tunnel before the Henkel restriction, the third problem of the day finally came. Scootering with the flow at perhaps  1 m/sec, the corner of my left pocket on my drysuit got caught on the tip of a rock and ripped a 3cm x 3cm hole. I could feel the chilly water flooding into my suit, so I stopped immediately, and within 10 seconds I lost my trim and buoyancy and was kneeling on the floor like in my Open Water class.

I told myself to “stop and think!” As in all the training we have done, I realized this was not an immediate life threatening situation, but the snowball could start rolling if I did not act correctly in a calm way. I checked my computers and used my primary light to get Derek’s attention and told him my drysuit was done for with the universal hand signal. Then I put some gas into the wing, but I was still on the floor. With more gas into the drysuit, I started moving again, in a vertical fashion. 

As you all can imagine, I had to put myself on the floor again at the Henkel. It is not extremely tight if you choose the right path, but with the DPV and camera and the Global Underwater Explorers (GUE)-configured JJ-CCR on my back, I was worried that I might not get out of the cave smoothly. Usually I stay very calm during a dive, but the depth was 32 m/105 ft, and the clock was ticking I was unsure of what would happen with that hole in my drysuit. I dumped all the gas in my suit and carefully crawled out of the restriction. Luckily, visibility is not a problem in Ginnie’s main tunnel because of the flow, and I can verify that a v-drill is easier when you have your belly on the ground.

To be honest, this was when I just completely got out of the panic mode. I knew I was getting closer to the surface, and I would be fine as long as I stayed focused. I inflated my suit, but as soon as I tried to stay horizontal, the gas leaked out from the hole. So, I put more gas into the loop and started being dragged by my scooter like SLAVE I in Star Wars, while still having to kick the whole time against the weight of my feet. 

That was when I started to feel cold. I could not imagine what this would have been like if I had been in a freezing cold cave like Orda, where the low temperature would have already killed me. All I could do was focus on scootering and choosing the taller passage if possible, in order to avoid messing with my buoyancy. Derek retrieved my bailout tank on the way out, and we made it back to the cavern in about 145 minutes, which is almost twice the time it usually takes.

My dive profile

There was no one else in the cavern when we started doing our longer-than-planned deco. I inflated my suit and knelt down on the rock at 6 m/20 ft so I could at least keep my torso relatively dry. I was getting colder and colder since I was not moving at all, but thanks to the 21ºC/70ºF degree spring water, my mind was still clear enough to think about getting a rental drysuit at Extreme Exposure and coming back in two days. After about 40 minutes of deco, we got back to the surface, and I had a really hard time walking back to my truck with all the water in my suit. What is worse, even the clouds started crying for me (or perhaps for my drysuit).

Drysuit full of water with the hole. Notice the rip on the top of the left pocket.

A fully flooded drysuit is something we always had talked about in our training but would never practice on purpose. When it actually happens, one can lose his trim and buoyancy within seconds, resulting in much more serious problems; for example, navigation, extended deco time, and hypothermia. 

In retrospect, I think there are 3 reasons why it happened to me:

  1. I was diving a Kirby Morgan M48 Mod-1 full face mask to facilitate better communication with my model, but the vision was relatively limited,and I did not pay enough attention to the surroundings;
  2. I had two big video lights in my pocket, and the pocket was exposed as I dropped my sidemount bailout tank;
  3. I should have gone slowly or maybe swum in more restricted areas.

I consider myself lucky that I got nothing but cold and lost nothing but an old drysuit, and thanks to Derek who made the process easier. It could have been a totally different story in another cave with a silty bottom or freezing cold water. However, out with the old, in with the new; it was time to get another drysuit.

Have you or a teammate ever had a “close call” while diving? Please take a few minutes to complete our new survey: Close Calls in Scuba Diving 

Fan Ping is a Chinese photographer and filmmaker based in Atlanta, Georgia, USA, and is dedicated to showing the beauty of the underwater world to people through his lens. He is specialized in combining artistic elements with nature and complex lighting skills in overhead environments, and this artistic style has brought him international acclaim, including awards from many major underwater photo/video competitions. You can follow his work on Facebook and Instagram: Be Water Imaging.

The best of Fan Ping’s work can be purchased at:

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