What Is Freediving?
Peter Letts Apr 19, 2022
A beginner's guide to breath-hold diving
What Is Freediving?
Freediving is underwater diving on a single breath, combining relaxation, efficient movement, equalisation and disciplined buddy safety.
Unlike scuba diving, a freediver does not breathe from a cylinder underwater. Unlike ordinary snorkelling, freediving includes intentional breath-hold descents, underwater movement and controlled returns to the surface. It can be recreational, photographic, competitive or part of activities such as spearfishing—but safe practice always depends on training and direct buddy supervision.
A long human tradition
Freediving is older than the modern sport
People have used breath-hold diving for food gathering, pearls, sponges and cultural practices for centuries. Today's organised sport adds formal disciplines, measured performances, specialist coaching and standardised safety procedures.
Many people never compete. They freedive to move quietly through the ocean, photograph marine life, explore shallow reefs, improve water confidence or enjoy the focus that comes from calm, deliberate movement.
Physiology and technique
How freediving works
A freedive is a balance between oxygen use, carbon-dioxide build-up, changing pressure and the diver's ability to stay relaxed and move efficiently. These are trainable skills, but personal limits vary from day to day.
Breath-hold and gas exchange
The body keeps using oxygen during a breath-hold while carbon dioxide rises. The urge to breathe is strongly influenced by carbon dioxide; it is not a reliable measure of how much oxygen remains.
The diving response
Facial immersion and breath-holding can slow the heart and reduce blood flow to some peripheral tissues. On deeper dives, blood shifts towards the chest help the body respond to compression.
Pressure and equalisation
As depth increases, air spaces compress. The ears and mask must be equalised early and gently. Pain or failed equalisation is a reason to stop the descent—not something to push through.
The ascent
Ambient pressure falls on ascent, and oxygen partial pressure can fall rapidly near the surface. Loss of motor control or blackout may occur close to the surface or just after surfacing, which is why an attentive buddy is essential.
Pool and depth disciplines
What kinds of freediving are there?
Freediving includes several recognised disciplines. Beginners normally learn foundational pool and line-diving skills; specialised record formats are not routine beginner activities.
| Setting | Discipline | What the diver does |
|---|---|---|
| Pool | Static apnea (STA) | Holds their breath while resting at the surface under direct supervision. |
| Pool | Dynamic apnea (DYN, DYNB or DNF) | Travels horizontally with a monofin, bifins or without fins. |
| Depth | Constant weight (CWT or CWTB) | Descends and ascends using a monofin or bifins without pulling on the line except as permitted at the turn. |
| Depth | Constant weight no fins (CNF) | Descends and ascends by swimming without fins and without pulling on the line. |
| Depth | Free immersion (FIM) | Pulls on the line to descend and ascend, without propulsion fins. |
| Specialised formats | Variable weight and no-limits | Use weighted descent systems and assisted ascent methods. These are specialist record disciplines, not normal entry-level training. |
Three different activities
Freediving, snorkelling and scuba diving
| Activity | How breathing works | Typical focus |
|---|---|---|
| Snorkelling | Breathes through a snorkel while face-down at the surface, with optional short duck dives. | Surface observation and relaxed swimming. |
| Freediving | Uses one breath for a planned descent, underwater phase and ascent. | Quiet exploration, skill development, photography or sport. |
| Scuba diving | Carries a supply of compressed breathing gas and breathes continuously underwater. | Longer underwater visits with scuba-specific training and procedures. |
Safety is a system
Freediving should never be practised alone
The central rule is simple: every breath-hold in water needs a trained buddy who is close enough, attentive enough and prepared to assist. A person merely being somewhere at the beach or pool is not adequate supervision.
- Use direct buddy supervision and appropriate one-up, one-down procedures.
- Never deliberately hyperventilate before a breath-hold.
- Equalise early and gently; turn if equalisation fails or pain develops.
- Build depth and duration conservatively, with suitable surface recovery.
- Match exposure protection, weighting and the dive plan to the conditions.
- Practise pool apnea only under qualified, direct supervision and follow pool rules.
- Complete the required medical questionnaire and seek medical clearance when directed.
Hypoxia and blackout
Low oxygen can cause loss of motor control or consciousness, sometimes with little warning. A trained buddy and effective rescue response are critical.
Pressure injury
Ear, sinus, mask and lung barotrauma can occur when pressure is not managed correctly. Lung squeeze is associated with depth, compression, individual adaptation and technique—not simply descending too quickly.
Environmental hazards
Cold, waves, current, poor visibility, boats, fishing line and marine life can change the risk of a session. Conditions must remain within the team's training and experience.
Nitrogen-related risks
Nitrogen narcosis and decompression sickness are uncommon in typical shallow recreational freediving, but DCS is possible after repetitive deep breath-hold exposures. Deep training requires specialist planning.
Keep the setup simple
What equipment do freedivers use?
Mask and snorkel
A comfortable, low-volume mask is easier to equalise. A simple snorkel is useful at the surface.
Fins
Long-blade bifins or a monofin can improve propulsion, but fit, technique and suitable stiffness matter more than length alone.
Wetsuit and weights
Exposure protection helps manage temperature. A rubber belt and carefully selected weights may be used to achieve an appropriate buoyancy plan.
Training equipment
A visible buoy, weighted line and—when required for line diving—a suitable lanyard create a structured depth-training station.
Learn the system, not just the breath-hold
How to start freediving in Sydney
Start with a recognised course taught by a qualified freediving instructor. A structured beginner course should combine knowledge development with confined-water practice, open-water technique, equalisation, recovery breathing, buddy supervision and rescue skills.
Abyss Scuba Diving's PADI Freediver Course in Sydney combines eLearning, confined-water training and two supervised ocean sessions, subject to conditions and successful completion of the required skills. You can also compare Sydney freediving training options before choosing a course.
See the course environment
PADI Freediver training in Sydney
Common beginner questions
Freediving FAQs
Is freediving just deep snorkelling?
No. Snorkelling is mainly a surface activity. Freediving uses planned breath-hold descents and requires specific training in equalisation, recovery, buddy supervision and rescue.
Do I need to hold my breath for a long time before I start?
No. Beginner training develops comfort, technique and safety from your current level. Performance varies widely and should never be compared or forced.
Do freedivers breathe out underwater?
Freedivers generally hold the breath during the underwater phase, but breathing and recovery procedures should be learned from an instructor. Avoid experimenting with exhalation strategies or breath-hold limits without direct supervision.
How deep do beginner freedivers go?
There is no single target depth. Progress depends on equalisation, comfort, conditions, course standards and instructor judgement. A safe, controlled turn is more important than a number.
Can I practise breath-holds alone in a pool?
No. Never practise breath-holding in water alone. Use qualified, direct supervision and comply with the facility's rules; passive observation from elsewhere is not enough.
Is freediving safe?
Freediving has inherent risks, including blackout, drowning and pressure injury. Good instruction, direct buddy supervision, conservative progression and sound conditions reduce risk but cannot eliminate it.
Further reading
- PADI: Freediving program information
- Breath-Hold Diving—The Physiology of Diving Deep and Returning (peer-reviewed review)
- Divers Alert Network: Decompression sickness while freediving
Learn freediving safely in Sydney
Build calm, efficient technique and practise the buddy and rescue procedures that responsible breath-hold diving requires.
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