Nov 145 min read

Freediving Safety: What You Need to Know to Dive Safer and Smarter

Freediving is more than a sport—it’s an experience that lets you explore the ocean’s beauty on a single breath. But with the thrill of freediving comes the need for caution. Without the right training, understanding of risks, and safety measures, freediving can quickly become dangerous. Fortunately, recent research and new tech can help us dive deeper, longer, and, most importantly, safer. Let’s break down what you need to know about freediving risks and how to keep your dives safe and enjoyable.

The Biggest Risks in Freediving

Freediving is all about challenging yourself, but it also challenges your body in ways you might not expect. Here are some of the main risks to be aware of:

Running Out of Oxygen (Hypoxia): As you dive, your body uses up the oxygen in your blood. Freedivers can go a surprisingly long time without breathing, but the longer you’re under, the more oxygen depletes. If your oxygen drops too low, you risk blacking out underwater. Hypoxia is one of the leading causes of freediving accidents, and it can happen suddenly—especially as you return to the surface.
Too Much Carbon Dioxide (Hypercapnia): Holding your breath for long periods also builds up carbon dioxide (CO₂) in your blood. Normally, rising CO₂ levels are what trigger the urge to breathe. Freedivers train to control this reflex, but too much CO₂ can cause mental fog, dizziness, and even blackouts. Pushing CO₂ tolerance too far can be risky if you don’t know your body’s limits.
Pressure Injuries (Lung Squeeze and Barotrauma): The deeper you go, the higher the water pressure. This pressure compresses your lungs and can lead to lung squeeze, where air sacs in the lungs are damaged. If you don’t equalize properly, pressure can also harm your ears and sinuses. While experienced divers often learn to handle deeper pressures, beginners need to be cautious as they develop these skills.
Decompression Sickness (DCS): Though more common in scuba, DCS can happen to freedivers who take repeated deep dives with short recovery times. It’s caused by nitrogen bubbles building up in the bloodstream, and it can be serious, affecting joints, lungs, and even the brain.

Factors That Increase Your Risk

Some personal factors can make freediving riskier, so it’s important to understand what they are and how to manage them:

Inexperience and Lack of Training: Freediving may look simple, but it requires skill and technique, especially for deep or extended dives. Experienced divers know how to manage their oxygen and CO₂ levels, conserve energy, and handle pressure. Beginners who dive without proper training face a higher risk of accidents.
Higher Body Fat Percentage: Research from Undersea & Hyperbaric Medicine shows that body fat doesn’t just affect physical appearance—it can also affect how long you can hold your breath. Higher body fat tends to reduce oxygen efficiency, which can shorten dive time and increase hypoxia risk. So, divers with leaner body compositions may actually have a slight edge in freediving endurance.
Limited Lung Capacity: Lung capacity directly impacts how much oxygen you can store for a dive. Divers with larger lung capacities can hold more air, allowing them to stay under longer. If you want to boost your dive times safely, lung training can be a great addition to your routine.
Short Recovery Between Dives: If you don’t give yourself enough time to rest between dives, your oxygen and CO₂ levels won’t fully reset, which can make your next dive riskier. Successive deep dives with too little recovery time increase the likelihood of hypoxia and exhaustion.

Tips for Safer Freediving

Freediving safety has come a long way, thanks to better understanding of the body’s limits and wearable technology. Here are some tips to help you dive safely and confidently:

Train with a Professional: One of the best ways to stay safe is by learning from a certified freediving instructor. They’ll teach you essential techniques like equalization, breath-hold exercises, and safety protocols. An instructor can also help you gauge your limits and give you feedback on your form, which will pay off in both safety and performance.
Wear a Dive Monitor: New wearable tech is changing the game for freedivers. Devices that measure blood oxygen (SpO₂) and heart rate allow you to track your body’s status in real-time. According to research by Mulder et al. (2021), wearable monitors can alert divers to unsafe oxygen and CO₂ levels, letting you know when it’s time to resurface. These devices can be a literal lifesaver.
Master Relaxation Techniques: One of the secrets to better freediving is learning how to relax. Anxiety and stress burn through oxygen faster, so staying calm helps conserve it. Practice deep breathing exercises before you dive, and try to keep a relaxed rhythm while underwater. Visualization and meditation can also help you feel centered and focused.
Increase Your Lung Capacity: You don’t have to go super deep to train your lungs. Simple exercises, like deep diaphragmatic breathing and breath-hold practices, can help you gradually expand your lung capacity. Over time, better lung function means more oxygen for each dive, helping you stay underwater longer and safer.
Take Your Time to Recover: It’s tempting to jump back in for another dive right away, but giving your body time to recover makes a big difference. Rest until you feel your breath and heart rate return to normal. A good rule of thumb is to wait at least twice as long as your previous dive before going again, giving your oxygen levels a chance to reset.
Always Dive with a Buddy: Freediving solo is one of the biggest no-no’s in the sport. A buddy can monitor you, offer help if needed, and provide immediate assistance in case of blackout or other issues. The “one-up, one-down” system is a popular safety practice: while one person dives, the other stays at the surface to watch and be ready to assist.

Myths to Watch Out For

Freediving has its fair share of myths, and some of these can lead to risky practices:

Myth #1: Hyperventilating before a dive is helpful. While it might seem like breathing rapidly would let you hold your breath longer, it can actually trick your body into holding out too long, increasing your risk of hypoxia and blackout. Divers should avoid excessive hyperventilation.
Myth #2: Experienced divers don’t need buddies. No matter how skilled you are, a dive buddy is essential. Even the most seasoned freedivers can have unexpected issues, and a buddy is there as a safety net.
Myth #3: Longer dives are better. Focusing only on dive time can make you ignore your body’s warning signs. Prioritize safety and skill-building over pushing for longer dives.

Final Thoughts

Freediving is a beautiful and rewarding sport, but staying safe requires understanding the risks and respecting your body’s limits. From managing oxygen and CO₂ levels to practicing good recovery, small habits can make a big difference in your freediving experience. With the help of wearable tech, solid training, and safe practices, you can enjoy freediving with confidence, knowing you’re prepared for whatever the ocean brings.

For further reading on freediving safety, check out Mulder et al. (2021) or Undersea & Hyperbaric Medicine, where you’ll find more on the science behind safe freediving. With a safety-first approach, freediving can be an incredible way to connect with the underwater world. Dive safe, dive smart, and enjoy every moment of your journey beneath the surface.

References

Mulder, E., Dujic, Z., Schagatay, E., & Sieber, A. (2021). New scientific methods in breath-hold diving research. Freiberg Online Geoscience, 58.

Undersea & Hyperbaric Medicine. (n.d.). Identifying Risk Factors and Safety Strategies in Freediving Through Physiological Research and Wearable Technology.