Predicting Performance in Competitive Apnoea Diving, Part I - Static Apnoea
Authors: Erika Schagatay
DOI / Source: https://pubmed.ncbi.nlm.nih.gov/22753202/
Date: 01 June 2009
Reading level: Intermediate
Why This Matters for Freedivers
This paper is basically a “map” of what actually determines how long you can hold your breath in static—not just willpower. It helps you focus your training on the things that really move the needle (oxygen stores, oxygen use, and tolerance to rising CO₂/low O₂), and it also quietly reinforces safety: some performance strategies (especially heavy hyperventilation or aggressive packing) can increase risk if used carelessly.
Synopsis
Competitive freediving has improved at a crazy pace, and static apnea is the purest version of the sport: no fins, no depth, no technique variables—just you, your physiology, and your ability to stay calm while your body screams at you to breathe. This review asks a simple question: what predicts elite static performance, and which of those factors can realistically be trained?
The author groups the limits of static into three big levers:
1) Total oxygen (and gas) storage 2) Tolerance to asphyxia (how low O₂ and how high CO₂ you can tolerate without losing control or consciousness) 3) Metabolic rate (how fast you burn oxygen)
From there, it breaks each lever into the real-world pieces freedivers recognize.
1) Gas storage: where the oxygen “lives”
- Lungs: Bigger lung volume helps, especially in static where oxygen use is low. In very simple terms, more air can mean more time—if you can keep metabolism calm.
- Blood: Oxygen stored in the blood depends largely on blood volume and hemoglobin concentration. The paper discusses how these can differ between divers and non-divers, and how some changes may be training-related.
- Spleen contraction: The spleen can act like a temporary “red blood cell booster,” squeezing extra cells into circulation during repeated apneas. That can slightly increase oxygen-carrying capacity and buffering for later breath-holds—one reason warm-up apneas can help.
- Tissues: Oxygen stored in tissues (especially myoglobin in muscles) matters more for dynamic disciplines, but it’s still part of the total picture.
2) Tolerance: handling CO₂, low O₂, and the urge to breathe
Static has a very recognizable structure: - an early “easy-going” phase where you feel fine, - followed by a “struggle phase” where involuntary breathing movements build and mental control becomes the skill.
The paper highlights that while CO₂ is a major driver of discomfort in non-divers, trained divers often show a different balance: they can tolerate higher CO₂ and lower O₂ before losing control. It also emphasizes that the length of the struggle phase isn’t just physiology—it’s influenced by motivation, technique, and mental strategy.
3) Metabolic rate: the underrated superpower
One of the most practical takeaways is that elite static performance often depends on getting oxygen use below normal resting levels. That means: - deep relaxation, - minimizing movement, - staying warm and comfortable, - and avoiding mental stress (because stress chemistry is expensive).
Preparatory breathing and “tools” (with trade-offs)
The review discusses common preparation strategies: - Breathing patterns before the attempt that aim to raise oxygen and reduce CO₂ - Lung packing (glossopharyngeal insufflation) to increase lung volume
But it also points out the downsides: packing increases chest pressure and can reduce venous return, and aggressive CO₂ reduction can remove your early warning signs—both of which are relevant for safety, especially outside controlled competition environments.
Overall, this is a classic freediving physiology review: it doesn’t claim one magic variable explains everything, but it lays out the full stack—how much oxygen you start with, how slowly you spend it, and how well you tolerate the signals that try to stop you.
Abstract
This review examines which factors predict performance in competitive apnea diving, focusing on static apnea. Across all apnea disciplines, performance depends on the ability to prolong breath-hold duration by increasing total gas storage, improving tolerance to asphyxia (rising CO₂ and falling O₂), and reducing metabolic rate. These main factors are further divided into physiological and psychophysiological components, and the paper discusses which are likely influenced by training. It is the first of two reviews; the second addresses dynamic distance and depth disciplines.