How long can you hold your breath underwater? Ten seconds? Twenty? Experienced freedivers can remain underwater for up to five minutes while moving. That’s five minutes swimming around under the surface, without the help of an oxygen tank.
An alternative to the ever-popular scuba diving, freediving has been practised since ancient times, when it was used to harvest pearls and sponges, and gather food. But while the invention of scuba gear means the activity is no longer necessary, it is still an amazing, and fun sport, which teaches self-reliance at the same time as revealing sub-aquatic secrets.
It’s also a great way to escape Hong Kong’s scalding summer temperatures: underwater, you lose body heat 25 times faster that you would standing on the shore.
While that’s great for cooling off, it can cause other issues.
International Association for Development of Apnea (Aida) and Professional Association of Diving Instructors (Padi) master freediving instructor Suzanne Lim, from Freediving Planet Hong Kong, explained that being cold increases our metabolism, which means we use more oxygen. And the more oxygen you use, the less time you can spend underwater.
Lim, one of the founders of Freediving Planet, a freediving organisation with centres in Hong Kong, and the Philippines, says insulation, therefore, is very important.
“Freedivers have wetsuits with air bubbles trapped inside. Body heat warms up the air bubbles. This insulates the freediver,” explains Chris Cheung, president of the Hong Kong Freediving Association. Cheung is an Aida and Padi Master Freediving Instructor, and a Hong Kong freediving record holder.
Even with body temperature taken care of, freedivers need to find ways to conserve as much energy as possible so they don’t run out of breath. And this is where some specialist equipment is required, in the form of bi-fins or monofins.
“Freediving fins are 80 to 90 cm long,” says Cheung. “This allows the diver to propel themselves more effectively. The monofin [which looks like a dolphin’s tail] is used by free divers for even more efficient propulsion. However, it requires extensive training and it is less manoeuvrable.”
Such fins help freedivers stay underwater longer, as they enable them to move further without using much energy. But not all divers want to move while they’re down in the deep blue sea. One discipline, static apnea, tests a diver’s ability to stay underwater without moving. The current world record is 11 minutes and 35 seconds, set by Stéphane Mifsud from France. While we’re talking records, the current record for the deepest freedive is 300 metres – the height of the Eiffel Tower – shared by Mateusz Malina from Poland and Giorgos Panagiotakis from Cyprus.
You might be thinking that all of this sounds a bit risky, but both instructors are quick to point out that freediving is a safe water sport.
“There is a strict partner system, buoyancy control, and a safety cable known as a lanyard.” Lim explains. “You never go freediving alone. There is always another partner at the surface, keeping watch of the other partner. Your weight belt is set to maintain neutral buoyancy at 10 metres below the surface. This makes sure that the diver can be easily brought back to the surface.”
Cheung adds: “Freedivers will attach themselves to a vertical stainless steel cable, connected to the bottom, using a lanyard. If the diver does not surface in a certain length of time, the surface crew will pull the diver up using the cable.”
Of course, as with all sporting activities, there are risks. “If a free diver has an oxygen saturation of less than 40 per cent, he might black out,” says Cheung. “That’s the body’s defence mechanism, because in this state, oxygen is used up at an extremely slow rate.
“His heart will still be beating and he will have minimal brain activity, but even so, a simple smack to the face or just calling his name will be more than enough to wake him.”
Cheung points out that there is a less than two per cent chance of a blackout due to lack of oxygen. And Lim is quick to say that it has never happened at Freediving Planet Hong Kong. And despite the tiny, literal risk of this being a heart-stopping activity, Cheung says freediving is more like yoga than it is other extreme sports.
“The training in yoga of relaxation, breathing, and flexibility is helpful,” he says. “Relaxation can lower oxygen consumption. As a freediver descends, water pressure increases, compressing the lungs. But flexibility makes the lungs less susceptible to injury.”
Lim agrees, saying. “I practise yoga everyday to improve flexibility, breath control and relaxation.”
Cheung also says that freediving is less restrictive than other water sports. “In scuba diving, you focus on your equipment. In freediving, your body is the equipment, giving you more freedom,” he says.
Freediving allows other freedoms, too, especially when you travel, and not just because you don’t need to carry as much.
“In Tonga, only freedivers are allowed to swim with whales,” says Cheung. “With no tanks, you don’t make any bubbles, and that makes freediving ideal for close contact with marine life. I swim close to fish, crabs, even small rays, and they sometimes don’t even notice me.”
If you like the sound of this sport, contact the Hong Kong Freediving Association at firstname.lastname@example.org, or call them at 5126 1208. For training in English, call 5592 5500 or email email@example.com.