Loss of Motor Control and/or Loss of Consciousness during Breath-Hold Competitions

Abstract

Since the first official world championships in breath-hold diving (1996), a sport has developed where the athletes compete in various disciplines of breath-hold diving. One of the rules is that the diver should surface from a dive without showing any signs of hypoxia. Depending on the severity of hypoxia, a diver may suffer disqualifying signs such as loss of consciousness (LOC) or loss of motor control (LMC), the latter including signs such as confusion, affected postural control, spasms or speech problems. Data was collected from the results of the major international competitions following AIDA guidelines (Association International pour le Dévelopment de l'Apnée) in 1998, 2001 - 2004. The data was analyzed for frequency of LOC and LMC during constant weight diving and during static apnea. In constant weight diving, the diver swims down (and up) as deeply as possible along a vertically suspended rope (current record 105 m). In static apnea, the diver strives for maximum duration, floating motionless face down in a pool (current record 8.58 min). A total of 601 static apnea (SA) performances and 596 constant weight dives were judged in the six competitions. On average, 10 % of SA, and 11 % of CW performances were disqualified due to signs of hypoxia. For the competitions in 2002 - 2004, a distinction was made in the rules between LOC and LMC; of a total number of 355 SA performances, 1.1 % resulted in LOC, while 9.6 % resulted in LMC. For CW, the number was 344 with 6.1 % LOC and 6.1 % LMC. Despite the relatively high incidence of dramatic signs, it is noteworthy that there have been no reports of fatal accidents or permanent injuries from any of the above-mentioned competitions. This descriptive paper shows a relatively high incidence of disqualifications due to signs of hypoxia in breath-hold competitions 1998 - 2004.

Apnea - diving - drowning - hypoxemia - hypoxia

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