Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Bradycardia during human diving.

P G Landsberg

    South African Medical Journal = Suid-Afrikaanse Tydskrif Vir Geneeskunde
    |April 5, 1975
    PubMed
    Summary
    This summary is machine-generated.

    The diving reflex causes bradycardia (slow heart rate) in divers, potentially conserving oxygen. However, extreme bradycardia during prolonged breath-hold dives can indicate a dangerous asphyxial response.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Evaluation of cyclooxygenase 2 inhibitor use in patients admitted to a large teaching hospital.

    Internal medicine journal·2003
    Same author

    Evaluation of dosage adjustment in patients with renal impairment.

    Internal medicine journal·2003
    Same author

    Alveolar and peripheral venous gas changes during breath-hold diving.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·1982
    Same author

    Decompression sickness in South African sport divers.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·1979
    Same author

    South African underwater diving accidents, 1969-1976.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·1976
    Same journal

    Clinical practice guidelines for the management of fever and neutropenia in South African children and adolescents with cancer.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·2026
    Same journal

    The changing fortunes of the District Health System in SA (1994 - 2020): A retrospective review.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·2026
    Same journal

    Early Online.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·2026
    Same journal

    LDL-cholesterol targets and lipid-lowering therapies - a plea to medical schemes and the Council for Medical Schemes.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·2026
    Same journal

    A rare case of paraneoplastic dermatomyositis secondary to smouldering multiple myeloma referred for proteinuria.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·2026
    Same journal

    Analysis of adverse events following COVID-19 vaccination and infection: A retrospective, comparative cohort study using a claims database from Discovery Health, a managed care organisation in South Africa.

    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde·2026
    See all related articles

    Area of Science:

    • Physiology
    • Marine Biology
    • Diving Medicine

    Background:

    • The diving reflex, characterized by bradycardia, is a known oxygen-conserving mechanism in humans and diving animals.
    • The exact physiological and nervous pathways of the diving reflex are not fully understood.
    • Accentuated diving reflexes can potentially lead to fatal outcomes.

    Purpose of the Study:

    • To investigate the heart rate response during breath-hold and SCUBA dives in male divers.
    • To compare heart rate changes at various stages of diving (resting, breath-holding, hyperventilating, underwater swimming).
    • To explore the potential dual nature of bradycardia during diving as either a protective reflex or an asphyxial response.

    Main Methods:

    • Investigated 8 male divers (average age 34) during breath-hold dives to 3.3 meters in a swimming pool.

    Related Experiment Videos

  • Recorded heart rates at different stages: surface rest, breath-holding, hyperventilation, and underwater swimming.
  • Included extreme breath-hold endurance tests (135 seconds) for two divers.

    • Main Results:

    • All divers exhibited tachycardia after hyperventilation and bradycardia (lasting 80-100 seconds) after breath-hold diving.
    • Extrasystoles were observed in some divers during breath-hold dives.
    • Prolonged submergence led to extreme bradycardia (24/min) and central cyanosis.

    Conclusions:

    • Bradycardia during diving can be a physiological oxygen-conserving reflex.
    • Alternatively, extreme bradycardia may signify the onset of a pathophysiological asphyxial response.
    • Further research is needed to fully elucidate the mechanisms and implications of the diving reflex.