The purpose of this study is to investigate the heart rate adaptations during deep dave diving with MCCR (mechanical closed circuit rebreather). Previous studies on this matter have not been conducted to the depths reached in this study and most of them have been conducted inside hyperbaric chambers trying to recreate the immersion conditions. The data collection took place during the exploration of two hydrogeological sites by a professional cave diver. The recordings were made using a SCUBAPRO GALILEO SOL® dive computer capable of monitoring the heart rate, with a sampling interval of 0,25 Hz. The data collected confirm a direct relationship between the increase in diving depth and the increase in the detected heart rate.


Scuba diving, Cave diving, Autonomous nervous system, Heart rate analysis,


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