Hypoxic Training Policy

Hypoxic training refers to adapting to a reduced level of oxygen, simply put, it involves holding your breath as long as possible. Artistic Swimming requires swimmers to practice hypoxic training (ie. training while holding your breath) due to the nature of the sport. However, athletes and coaches need to be aware of the consequences this practice may involve, and know how to minimise the risk of Shallow Water Blackout. 

Regular hypoxic training (threshold training) is an important component of an artistic swimmer’s development but needs to happen in a safe and controlled environment progressively, at an age and skill dependent level for each athlete.

The purpose of this policy is to reduce the risk of Shallow Water Blackout for all athletes of Alpine Synchro Artistic Swimming Club (“ASASC” or “the Club”) and follows the guidelines set by Artistic Swimming New Zealand. 

Amendments to our Hypoxic Training Policy

We reserve the right to review and amend this Policy from time to time.  Amendments will be effective immediately and ASASC has no obligation to notify you of such amendments.  We recommend that you check this page for amendments each time you revisit this website.

What is Shallow Water Blackout (SWB)?

SWB is a term describing the loss of consciousness arising from oxygen deprivation brought about by extended breath-holding, often associated with pre-submersion hyperventilation.

The term hypoxic blackout was first described in breath-hold divers who blacked out as they neared the surface after being underwater for a period of time. However, it can and does occur without submersion.

It is the level of carbon dioxide (CO²), In breath-holding activities, voluntary hyperventilation occurs when a swimmer intentionally takes a series of deep breaths venting off CO² with the greater than normal exhalations. This significantly reduces the blood CO² level while only marginally increasing oxygen concentrations in the body, thus increasing the potential for SWB. Involuntary hyperventilation can occur as a result of stress and physical exertion during a workout that pushes the swimmer beyond his/her maximum aerobic capacity.

When a person suffers a hypoxic blackout, they have generally held their breath and become unconscious through lack of oxygen before the level of CO² has built up to the critical level to trigger the signal to breathe. If this occurs on land, the person will recommence breathing once the CO² level is restored. However, in the water, the involuntary breathing by an unconscious person often results in drowning. There are documented cases of competent swimmers who lost their lives to hypoxic blackout.

This is a serious issue.

Synchro swimmers are at a higher risk of SWB by doing repeat efforts of extended underwater swims and extended figures training.

Coach’s Responsibilities

  1. Coaches will have a training session with the athletes to explain SWB and the feeling once a year and a refresher at the start of each term.They will go into depth with each of the swimming groups and pitch this at a level as to which the swimmers can understand.
  2. Adequate lung and hypoxic preparation should always be done prior to attempting threshold training – appropriate to the athlete’s age and ability – with a maximum of 25m underwater being recommended unless the athlete is experienced.
  3. Actively supervise any hypoxic training – the Coach will walk along poolside following the athlete closely for threshold underwater.
  4. Parents/other swimmers must not interrupt the Coach while they are focusing on underwaters. 
  5. Figures training – Pair up swimmers when practicing long figures so they observe and monitor each other when the Coach is working with another athlete.
  6. Routine/lift training – the Coach will observe each phase.
  7. Position underwater training earlier in the training session and allow adequate time for recovery. At least a two minute recovery time should be allowed before attempting another underwater swim.
  8. Swimmers MUST be advised by the Coach when they are permitted to start their underwaters to ensure the Coach knows the athlete is leaving the wall to attempt any threshold training.
  9. During breath-holding challenges, Coaches must make very clear to swimmers that if they need to breathe – they must come to the surface. There must be no pressure on swimmers to hold their breath beyond their limits. 
  10. Avoid breath-holding games and challenges wherever possible in the water – these are recommended to be done on land instead.
  11. If appropriate to your pool environment – lifeguards should be advised when any threshold hypoxic training is taking place.
  12. If a swimmer experiences any of the symptoms of SWB, they must be removed from the water immediately and lifeguards called to take over. They will not be allowed back in the water for training without approval from a medical professional.

Club Responsibilities

  1. Ensure all their Coaches clearly understand and implement this policy.
  2. Ensure all athletes are educated once a year and refreshed each term about the risks of hypoxic training and the symptoms of SWB.

Athlete’s Responsibilities

  1. Understand the risks and symptoms of SWB.
  2. Be aware they are trying to beat personal bests, not other athletes, with threshold underwater training.
  3. Never practice hypoxic training alone.
  4. Never hyperventilate prior to any underwater swimming – one deep breathe is all that is required. Do not take multiple deep breaths.
  5. Never ignore the urge to breathe.
  6. If feeling dizzy, tingling, seeing stars, feeling like they are going to faint or feeling numb, HEAD TO THE SURFACE AND BREATHE IMMEDIATELY, and let your Coach know.
  7. If they are asthmatic, keep their inhaler poolside with their Coach (while not strictly related to SWB, this is a good practice).