Terrific Freedive Mode

Text and Images by Nicolene Olckers
You are a Freediver. Take a look at your personal gear. It differs from what you would use as a scuba diver: simple designs or ergonomically shaped ones to improve underwater dynamics. The experienced freediver will most likely opt to have a low-volume mask, making for easier equalising using less air and effort to equalise their mask. Most freedivers also opt for the most basic snorkel, no snorkel and no mask.
The same can be said of choosing a dive computer. Having a dive computer will make your freediving safer and more enjoyable and help you track and improve your performance.
You are a Freediver. Take a look at your personal gear. It differs from what you would use as a scuba diver: simple designs or ergonomically shaped ones to improve underwater dynamics. The experienced freediver will most likely opt to have a low-volume mask, making for easier equalising using less air and effort to equalise their mask. Most freedivers also opt for the most basic snorkel, no snorkel and no mask.
The same can be said of choosing a dive computer. Having a dive computer will make your freediving safer and more enjoyable and help you track and improve your performance.

It's in the details
There are a few basic considerations when selecting a dive computer. Competitive divers will most likely opt for a watch-style computer that is small, dynamic, and consistently and accurately records their dives. It should at least be able to display your max depth, dive time and surface interval time, right?
Charl Marais, Freediving Instructor Trainer, had this to say. "I don't like fancy gadgets. The computer should work and not just stop working or malfunction suddenly. For me, reliability is key." He also preferred simplicity and insisted manufacturers/suppliers should provide proper service delivery in the diver's country. Charl mentioned the more essential features include the recording and display of surface interval times and bottom time. The computer should, at minimum, have one depth alarm and include a timer/stopwatch and chronograph. Using the timer/stopwatch and various alarm settings will let the diver know precisely where they are during their dive.
Timers or stopwatch features are often used by instructors when training students. Competitive freedivers often use timer and alarm features to know when to kick, when to do mouth-fill equalise and when to prepare to turn and head back to the surface.
Brittnee Engelbrecht, Freediver Staff Instructor at Apnea Addicts in Cape Town, said she uses her computer's stopwatch feature to time her students' dives. This enables her to know how long they have been under and when she should dive to the safety depth to check on them as they return to the surface. Or to know when she should dive down to fetch them when they overstay their dive time.
There are a few basic considerations when selecting a dive computer. Competitive divers will most likely opt for a watch-style computer that is small, dynamic, and consistently and accurately records their dives. It should at least be able to display your max depth, dive time and surface interval time, right?
Charl Marais, Freediving Instructor Trainer, had this to say. "I don't like fancy gadgets. The computer should work and not just stop working or malfunction suddenly. For me, reliability is key." He also preferred simplicity and insisted manufacturers/suppliers should provide proper service delivery in the diver's country. Charl mentioned the more essential features include the recording and display of surface interval times and bottom time. The computer should, at minimum, have one depth alarm and include a timer/stopwatch and chronograph. Using the timer/stopwatch and various alarm settings will let the diver know precisely where they are during their dive.
Timers or stopwatch features are often used by instructors when training students. Competitive freedivers often use timer and alarm features to know when to kick, when to do mouth-fill equalise and when to prepare to turn and head back to the surface.
Brittnee Engelbrecht, Freediver Staff Instructor at Apnea Addicts in Cape Town, said she uses her computer's stopwatch feature to time her students' dives. This enables her to know how long they have been under and when she should dive to the safety depth to check on them as they return to the surface. Or to know when she should dive down to fetch them when they overstay their dive time.

Keeping track of your dives and freediving
The research on decompression sickness (DCS) has also improved developments in dive computers. Although DCS is most often only attributed to scuba divers, it can also be a risk to freedivers. As the freediver descends to depth, the partial pressure of nitrogen in their lungs increases and is absorbed in their blood and muscle tissues. Suppose the excess nitrogen is not given time to dissolve from their system while at the surface; they, too, run the risk of DCS.
Taking proper surface intervals and planning is critical to safer freediving. Dives deeper than 50 meters should be limited to one deep dive daily. Should the diver repetitively dive to shallower depths and not spend enough time on the surface to outgas - freediving instructors and fun divers take note – he will risk developing DCS.
DCS can be caused by many factors, whether they are age, physical fitness, dehydration, physical injury, or body type. As a general rule, the surface interval should be twice that of the dive time when diving shallower than 30 meters. To calculate the surface interval time for diving deeper than 30 meters, the maximum depth is divided by 5.
The research on decompression sickness (DCS) has also improved developments in dive computers. Although DCS is most often only attributed to scuba divers, it can also be a risk to freedivers. As the freediver descends to depth, the partial pressure of nitrogen in their lungs increases and is absorbed in their blood and muscle tissues. Suppose the excess nitrogen is not given time to dissolve from their system while at the surface; they, too, run the risk of DCS.
Taking proper surface intervals and planning is critical to safer freediving. Dives deeper than 50 meters should be limited to one deep dive daily. Should the diver repetitively dive to shallower depths and not spend enough time on the surface to outgas - freediving instructors and fun divers take note – he will risk developing DCS.
DCS can be caused by many factors, whether they are age, physical fitness, dehydration, physical injury, or body type. As a general rule, the surface interval should be twice that of the dive time when diving shallower than 30 meters. To calculate the surface interval time for diving deeper than 30 meters, the maximum depth is divided by 5.

Dive logging and downloads
Being able to analyse aspects of their dive with a dive computer makes comparing dive time and speed can be highly beneficial to ensure that the diver's breath-hold is being used as effectively as possible. Some dive computers currently on the market also have configurable sampling/logging rates and ascent/descent indicators suitable for freediving. The dive logging system and sampling rates will enable you to break down each dive section separately to see where improvements can be made. Setting the sample rate of your dive computer to 1s allows a diver to record every second of the dive accurately. The ability to retrace your dive by downloading the data from your dive computer can set you free to concentrate on and develop your freediving performance in much finer detail.
Having a dive computer is essential to make freediving as safe as possible to extend your depth and time and monitor your progress during and after. You don't necessarily have to buy a new one; you can check if the dive centre in your area provides rentals. As in any extreme sport, the correct gear is vital for success. Knowing or learning how to use the equipment safely and adequately should be taken seriously. This applies to scuba diving, skydiving and to freediving.
Shearwater computer supplied by Dive Action, Cape Town. Reef Mask, Suunto D4i and Salvimar fins supplied by Dive Team, Simons Town. (Images are for demonstration purposes only.)
Being able to analyse aspects of their dive with a dive computer makes comparing dive time and speed can be highly beneficial to ensure that the diver's breath-hold is being used as effectively as possible. Some dive computers currently on the market also have configurable sampling/logging rates and ascent/descent indicators suitable for freediving. The dive logging system and sampling rates will enable you to break down each dive section separately to see where improvements can be made. Setting the sample rate of your dive computer to 1s allows a diver to record every second of the dive accurately. The ability to retrace your dive by downloading the data from your dive computer can set you free to concentrate on and develop your freediving performance in much finer detail.
Having a dive computer is essential to make freediving as safe as possible to extend your depth and time and monitor your progress during and after. You don't necessarily have to buy a new one; you can check if the dive centre in your area provides rentals. As in any extreme sport, the correct gear is vital for success. Knowing or learning how to use the equipment safely and adequately should be taken seriously. This applies to scuba diving, skydiving and to freediving.
Shearwater computer supplied by Dive Action, Cape Town. Reef Mask, Suunto D4i and Salvimar fins supplied by Dive Team, Simons Town. (Images are for demonstration purposes only.)
Posted in Alert Diver lite Editions, Dive Safety Tips, Women In Diving South Africa
Tagged with Freedive, Freedive modes, Dive computers, Wrist technology
Tagged with Freedive, Freedive modes, Dive computers, Wrist technology
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