DO THE COMPETITION RULES OF SYNCHRONIZED SWIMMING ENCOURAGE UNDESIRABLE LEVELS OF HYPOXIA

Recent anecdotal reports that some synchronized swimmers have become d izzy or disorientated towards the end of their performance, and in the worst cases fainted underwater, have caused concern. However, the rul es of synchronized swimming encourage slow performance of compulsory f igures, and an analysis of the competition placings and duration of un derwater sequences showed that the highest rankings were gained by slo wly performed compulsory figures and free programmes containing a long underwater sequence. The combination of breath-holding and the vigoro us exercise involved suggests that some of the symptoms complained of by the swimmers might be due to hypoxia. We therefore studied the alve olar gas tensions in nine members of the Great Britain National Squad immediately following the performance of set figures and the initial u nderwater sequence of their free routine in a swimming-bath. All were cyanosed after the underwater sequences of the free routine and report ed being mildly confused. The mean(s.d.) alveolar PO2 at this stage wa s 5.07(1.1) KPa, while three girls had an alveolar PO2 below 4 KPa, th e lowest being 3.67 KPa. These gas tensions suggest that potentially d angerous levels of hypoxia may develop during competitive synchronized swimming and that prolonged underwater sequences should not be encour aged.