抄録
The purpose of this study is to compare the circuratory function among three divers.One isJacques Mayol, a famous apnoeic diver of France and another two divers are male and femaleprofessional diver called Ama in Japan.The maximum underwater apnoeic time of Mayol was 4 minutes and 9 seconds while thatof male Ama was 2 minutes and 9 seconds, and female Ama 1 minute and 1 second.Remarkable bradycardia appeared in Mayol (Hreat Frequency, fH=34bpm) during apnoeicdiving.It was revealed from P0.1 test recordlng that the sensitivity to CO2 of male Ama waslower than that of Mayol, whose sensitivity was similar to that of ordinary Japanese adult.The vital capacity showed similar pattems.The exact mechanism of the extraordinary long apnoeic time of Mayol is still unknown.However, if the mechanism could be identified in the future studies and if longer apnoeicdiving in the ordimry divers could be realized with special training, man would be able to havewider underwater behavioural range.