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Updated: May 11, 2026

Investigation into Deep Breathing through Measurement of Ventilatory Parameters and Observation of Breathing Patterns
Published on: September 16, 2019
Electrocardiographic aspects of deep dives in elite breath-hold divers
F Lemaître1, V Lafay, M Taylor
1Centre d'Etudes des Transformations des Activités Physiques et Sportives (CETAPS, EA n03832), Faculty of Sports Sciences, University of Rouen, France. frederic.lemaitre@univ-rouen.fr
Abstract:
The cardiac diving response, 12-lead electrocardiogram (ECG) and the prevalence, time of onset, and possible associations of cardiac arrhythmias were examined during deep breath-hold (BH) dives. Nine elite BH divers (33.2 +/- 3.6 years; mean +/- SD) performed one constant-weight dive of at least 75% of their best personal performance (70 +/- 7 meters for 141 +/- 22 seconds) wearing a 12-lead ECG Holter monitor. Diving parameters (depth and time), oxygen saturation (SaO2), blood lactate concentration and ventilatory parameters were also recorded. Bradycardia during these dives was pronounced (52.2 +/- 12.2%), with heart rates dropping to 46 +/- 10 beats/minute. The diving reflex was strong, overriding the stimulus of muscular exercise during the ascent phase of the dive for all divers. Classical arrhythmias occurred, mainly after surfacing, and some conduction alterations were detected at the bottom of the dives. The BH divers did not show any right shift of the QRS electrical axis during their dives.
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