Dry apnea training guide

The Secret of Apnea: the Urge to Breathe (CO₂ vs O₂)

The urge to breathe is NOT caused by lack of oxygen, but by the natural build-up of carbon dioxide in the blood.

• At rest, your body consumes a minimal amount of oxygen.
• The brain detects the acidity generated by carbon dioxide (CO₂) and raises the alarm long before oxygen is low.
• Learning to accept the CO₂ build-up with relaxation is what lets you double your times without physical effort.
• Accept the signal without panicking: your body still has plenty of oxygen in blood and tissue.

Remember: the urge to breathe is a CO₂ alarm, not an oxygen emergency.

Golden Rule: NEVER Hyperventilate

Hyperventilating before a hold is the number one cause of blackouts and accidents in the water.

• Hyperventilation artificially clears CO₂ from your body but does NOT increase your oxygen reserve — the blood is already 98–99% saturated.
• By wiping out the CO₂ you remove your body's natural alarm: oxygen will fall to critical levels without you ever feeling the urge to breathe, and you lose consciousness with no warning.
• Correct ventilation: slow, gentle, diaphragmatic breathing — inhale over 4–5 s, exhale over 8–10 s without forcing.

Warning: Lethal danger: never hyperventilate before a hold, and NEVER train in the water without an attentive buddy.

Recovery Breathing Protocol (Hook Breathing)

How to breathe the moment a hold ends, to get oxygen to the brain immediately.

• On breaking the hold, take 3 hook breaths.
• Step 1: inhale fast and deep through the mouth, filling the chest.
• Step 2: make a micro-pause of half a second with the glottis closed, gently pressurising the chest to push oxygen towards the brain.
• Step 3: exhale passively through the mouth and repeat the cycle three times.
• Do not dump all the air at once in an empty sigh: always keep a minimum residual volume.

Three hook breaths after every hold secure your recovery and prevent post-apnea dizziness.

Total Relaxation of Throat, Neck and Jaw

Tension in the glottis is the most common mistake, and it doubles oxygen consumption.

• Closing the glottis should be a passive block, like the one that happens naturally when you swallow or hold your breath underwater.
• Do not clench your teeth or tense the masseters: let the lower jaw drop two millimetres.
• Rest the tip of your tongue softly on the palate, behind the upper incisors.
• Keep the cervical spine neutral, without pulling the chin to the chest or arching the neck back.

A relaxed throat keeps cerebral carotid flow clear and delays the distress.

Managing and Accepting Diaphragmatic Contractions

Contractions are harmless neuromuscular reflexes of the diaphragm. Learn to surf them.

• The first contraction marks the shift from the comfort phase to the struggle phase.
• Common mistake: tensing neck, throat and shoulders at the first jolt.
• Elite strategy: when a contraction hits, consciously loosen the jaw, open the chest and let the diaphragm move freely instead of resisting it.
• Track your time to the first contraction in the app: more rest beforehand and better relaxation push it later.

Do not fight the contraction: relax everything around it — face, shoulders, hands — and let it pass like a wave.

Progressive Body Scan

Invisible muscle tension burns up to 40% of your oxygen during a hold.

• In the first 60 seconds of the hold, work mentally down through your body:
• 1. Brow and eyelids: let go of any facial expression.
• 2. Tongue and jaw: let the lower jaw drop gently.
• 3. Neck and traps: check the head rests straight, without hyperextension.
• 4. Shoulders and arms: feel their weight on the surface.
• 5. Abdomen: loose and open to movement.

Apnea Walk Technique: Lactate Adaptation on the Move

Walking on a held breath builds mental and physical tolerance beyond pure static apnea.

• In Apnea Walk the quadriceps and calves consume oxygen actively while the diaphragm stays at rest.
• Always walk at a gentle, steady, rhythmic pace — roughly one step per second.
• Dissociate the body: keep arms, shoulders and face completely still while only the legs move.
• When you finish the set number of steps, slow down gently and do the three hook breaths, seated or standing with firm support.

Warning: Safety rule: train only on soft, clear ground — grass or mats. Never near kerbs or stairs.

Square Tables vs Progressive Tables

Choosing the right stimulus for the goal of your training cycle.

• CO₂ tables: the hold stays fixed (say 1:30) and the rest drops progressively from 2:00 to 0:45, to accumulate carbonic acid.
• O₂ tables: the rest stays constant (say 2:00) and the hold gets longer (say 1:30 to 3:00), to get used to low SpO₂ saturation.
• Square tables: identical holds and rests (say 8 × 1:00 with 1:00 rest). Ideal for building volume and consistency without excessive stress.

Chest Flexibility and Abdominal Vacuum (Uddiyana Bandha)

Elasticity of the diaphragm and rib cage to withstand lung compression.

• A flexible diaphragm reduces the pressure of contractions and helps prevent thoracic barotrauma.
• Abdominal vacuum exercise: on an empty stomach, exhale everything, lock the glottis and expand the ribs while sucking the abdomen up and in.
• Hold for 10 to 15 seconds without forcing, then release slowly.
• Stretch the rib cage and intercostals before dry training.

Warning: Advanced: dry land only and on an empty stomach. Never force it if you feel pain or dizziness.

Inducing the Mammalian Dive Reflex (MDR)

Triggers reflex bradycardia (pulse dropping below 45 bpm) and peripheral vasoconstriction.

• The dive reflex is triggered mainly through the trigeminal nerve thermoreceptors in the face and forehead.
• Practical tip: a towel soaked in cold water over the face two minutes before a session brings an immediate drop in heart rate.
• During the hold, the body shunts blood away from the limbs towards the heart and brain to stretch its autonomy.

Blood Shift Physiology and Thoracic Adaptation to Pressure

The mammalian mechanism that protects the lungs from being crushed below 30 m.

• At depth — or in dry residual-volume holds — pressure compresses lung volume below the anatomical residual volume.
• To avoid thoracic collapse, the circulatory system redistributes up to a litre of blood from the limbs into the alveolar capillaries.
• That thickened vascular bed acts as an incompressible hydraulic cushion protecting the rib cage.
• Training Uddiyana Bandha and FRC holds conditions the alveolar walls for this haemodynamic stress.

Lung flexibility is trained on land so you can be safe at sea.

Lung Packing (Glossopharyngeal Insufflation) and Safety Limits

Glossopharyngeal insufflation to go beyond total lung capacity (TLC) in competition.

• Mechanics: after a maximal inhalation, the mouth and tongue act as a piston, pushing extra gulps of air into the already pressurised lungs.
• Extra volume: allows 0.8 to 2.5 additional litres of air depending on the athlete's alveolar elasticity.
• Dangers and contraindications: packing raises intrathoracic pressure sharply, compresses the vena cava and reduces venous return to the heart, causing a drop in cardiac output and a risk of syncope from hypotension before the hold even starts.
• Golden rule in competition: never do more than 3 to 5 packs on dry land. It must be built up over months alongside chest wall elasticity stretching.
• Reverse packing (exsufflation): actively drawing air out at residual volume to train the blood shift response at simulated depth.

Warning: Extreme: excessive packing can cause pulmonary barotrauma, atelectasis or haemodynamic collapse. Forbidden for beginners.

Less is more: a relaxed pack of 3 pumps is a hundred times more efficient than forcing 15 with a rigid chest.

FRC and Residual Volume Training (Empty Lungs)

Simulating extreme depth (30 m – 60 m) on dry land through empty-lung holds.

• FRC (functional residual capacity): a hold after a passive exhalation, at resting respiratory level. Simulates the pressure of 15–20 metres.
• RV (residual volume): a hold after a maximal forced exhalation. Simulates the thoracic compression of more than 35–50 metres.
• Physiological advantage: it triggers diaphragmatic contractions in barely 15–25 seconds, so you can train mental tolerance to hypercapnia with very short total durations and minimal cerebral oxygen cost.
• Blood shift activation: it forces blood plasma from the periphery into the alveolar capillary bed, which helps prevent pulmonary oedema at sea.

Warning: Always sitting or lying on a soft surface (a bed or a mat). The risk of postural dizziness on standing up is high.

Empty-lung holds train the competition mindset in one minute what full lungs would need four minutes to train.

Extreme Lactic Acidosis Tolerance (DYN / DNF)

Managing neuromuscular fatigue and burning quadriceps without speeding up oxygen consumption.

• In dynamic apnea (with fins, DYN, or without, DNF), the muscles work in anaerobic glycolysis and produce lactic acid in quantity.
• The build-up of H⁺ ions lowers blood pH, which aggressively stimulates the medullary respiratory centre on top of the CO₂ signal.
• Competition strategy: segmental dissociation. Keep the upper body — shoulders, neck, jaw — in absolute relaxation (zero muscle tone) while the legs work at a steady, fluid cadence.
• Glide technique: in DNF, 70% of the distance is gained in the motionless hydrodynamic glide after the kick, saving up to 45% of ATP.

In dynamic apnea speed is not your ally: hydrodynamics and a relaxed upper body set the record.

Official Surface Protocol (AIDA / CMAS)

How to avoid the dreaded red card (DQ) after a maximal effort in official competition.

• The 15-second rule: once you break the surface you have a strict maximum of 15 seconds to complete the protocol unassisted.
• Exact sequence: 1. Remove mask or nose clip → 2. Look the head judge straight in the eye → 3. Make the OK sign with your fingers → 4. Say clearly and out loud: "I AM OK" (or "I'M OK").
• Fatal errors that cause disqualification:
• • Touching the water with your airways (mouth or nose) after surfacing.
• • Saying "OK" before removing the mask or goggles.
• • Hesitating or letting your head wobble, losing eye contact with the judge.
• • Leaning on or gripping the line or the pool edge with both arms.
• Automatic training: run the surface protocol at the end of EVERY dry training hold so your brain executes it subconsciously even under hypoxia.

The record does not end when you surface to breathe: it ends when the judge raises the white card.

Warm-Up Strategy: Warm-Up vs No Warm-Up

How to plan the 45 minutes before an official record or competition attempt.

• Strategy 1 (no warm-up, maximum reserve): the athlete does only gentle relaxation breathing and goes straight into the official attempt. Advantage: it preserves 100% of glycogen, avoids psychological fatigue and maximises the first bradycardia peak.
• Strategy 2 (one activation hold): a single short hold at 40% of maximum time, 15 minutes before the official attempt, to wake the mammalian dive reflex and peripheral vasoconstriction.
• Classic competition mistake: doing several intense test holds before the attempt, which saturates lactate receptors and drains the neurotransmitters of calm.

Neuro-Visualisation and Alpha/Theta Waves in Static Apnea

Reducing the metabolic cost of the brain, the organ that consumes 20% of the body's oxygen.

• Active thought and logical analysis (beta waves) burn oxygen fast.
• Cortical disconnection technique: instead of thinking about the time or counting seconds, move your attention to a continuous sensory flow — the sound of blood in your ears, the weight of gravity, the darkness behind your eyelids.
• Kinaesthetic anchoring: attach a word or physical sensation ("flow", "zero gravity") to the state of deep relaxation during your daily training, so you can summon it instantly on the start line.

In deep apnea the brain has to become a passive spectator, not a stopwatch.

Nutrition, Digestion and Caffeine

External metabolic factors that radically change your rate of oxygen consumption.

• Digestion: digesting costs an enormous amount of energy and oxygen. Always train after at least 2.5 to 3 hours fasting.
• Caffeine and stimulants: caffeine raises heart rate and increases baseline O₂ consumption. Avoid it 4–6 hours before training.
• Dairy and mucus: dairy and fatty foods thicken saliva and mucus in the upper airways.
• Hydration: dehydration thickens the blood and reduces the efficiency of oxygen transport.

Empty stomach plus good prior hydration equals a lower resting pulse and more comfortable holds.

The Final Inhalation in Three Stages

How to fill the lungs to 100% of vital capacity without creating tension in the breathing muscles.

• Stage 1 (abdominal, 60%): expand the diaphragm, pushing the stomach gently outwards.
• Stage 2 (costal, 30%): open the ribs sideways, filling the middle of the chest.
• Stage 3 (clavicular, 10%): raise the sternum and collarbones slightly, without hunching the shoulders.
• Closing: shut the glottis gently — the natural valve in the throat — keeping mouth and jaw completely relaxed.

Live Biofeedback: Compatible Heart Rate and Pulse Oximeter Sensors

Monitor your bradycardia curve and SpO₂ saturation in real time with standard BLE hardware.

• Garmin watches: turn on Broadcast Heart Rate on your Fēnix, Forerunner, Epix or Instinct to pair it with CAPNIA over Bluetooth.
• Heart rate straps: Polar H10 / H9 / Verity Sense, Wahoo TICKR, CooSpo and Decathlon give accurate electrocardiographic readings of extreme bradycardia.
• Finger and ring oximeters: BerryMed (BM1000/BM2000), Wellue O2Ring and Nonin 3230 transmit SpO₂ in real time and sound an alarm if saturation drops below the safety threshold.
• The full step-by-step guide with every model is in Settings › Supported Devices.

Real-time biofeedback teaches you to relax the autonomic nervous system consciously, by watching your pulse fall on the graph.

Hydration and Electrolyte Balance (Magnesium and Potassium)

Magnesium and potassium are essential to avoid cramps and muscle spasms under hypoxia.

• Apnea produces temporary acidosis and rapid peripheral vasodilation, which speeds up the loss of cellular water.
• Magnesium (bisglycinate or citrate) relaxes baseline muscle tone and lowers the neuromuscular excitability of the diaphragm.
• Drink water with a pinch of sea salt or electrolytes an hour before dry training.
• Avoid sugary drinks or acidic juices right before holds, to prevent reflux during contractions.

Why do I feel tingling in my hands or feet during a hold?

It is a normal physiological effect called peripheral vasoconstriction, caused by the dive reflex.

• Your autonomic nervous system narrows the blood vessels in your limbs to concentrate oxygen flow in the brain and heart.
• It is a positive sign that your body is shifting into oxygen conservation mode.
• It is not dangerous and it disappears within seconds of the first recovery breath.

How many days a week should I train with tables?

Rest for the central nervous system is essential in order to progress.

• Optimal frequency: 3 to 4 days a week, with at least one full rest day between intense sessions.
• Alternation: do not run high-intensity tables (maximal O₂ or Wonka) two days in a row.
• Alternate CO₂ table sessions, for tolerance, with pranayama relaxation and diaphragmatic breathing.

Why do I sometimes get a headache after training?

Post-apnea headache is usually down to CO₂-driven cerebral vasodilation or dehydration.

• Rising blood CO₂ dilates the cerebral arteries. When you start breathing abruptly again, the change in vascular pressure can produce a mild passing headache.
• Second cause: tension in the neck or jaw muscles during contractions.
• Fix: take three gentle hook breaths without over-pressurising, and drink a large glass of water with minerals after the session.

Is it normal to feel deeply sleepy after an intense session?

Yes: parasympathetic activation and falling cortisol induce deep relaxation.

• Vagus nerve stimulation and sustained bradycardia put the brain into alpha and theta wave states.
• It is a natural recovery response. Use it to rest, or train before bed to improve sleep quality.