| Autor: |
Brown CV; School of Health and Exercise Science, University of British Columbia Okanagan, British Columbia, Canada., Patrician A; School of Health and Exercise Science, University of British Columbia Okanagan, British Columbia, Canada., Tremblay JC; School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom., Brewster LM; School of Health and Exercise Science, University of British Columbia Okanagan, British Columbia, Canada., Barak O; Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia., Drvis I; Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia., Dujic G; Clinical Department of Diagnostic and Interventional Radiology, University Hospital of Split, Split, Croatia., Dujic Z; Department of Integrative Physiology, University of Split School of Medicine, Šoltanska, Split, Croatia., Ainslie PN; School of Health and Exercise Science, University of British Columbia Okanagan, British Columbia, Canada. |
| Jazyk: |
angličtina |
| Zdroj: |
American journal of physiology. Regulatory, integrative and comparative physiology [Am J Physiol Regul Integr Comp Physiol] 2024 Oct 01; Vol. 327 (4), pp. R442-R456. Date of Electronic Publication: 2024 Aug 05. |
| DOI: |
10.1152/ajpregu.00081.2024 |
| Abstrakt: |
The mammalian dive reflex, characterized by bradycardia and peripheral vasoconstriction, occurs in all mammals, including humans, in response to apnea. However, the dive reflex to a single, maximal, dry, dynamic apnea (DYN) and how it compares to a time-matched exercise control trial (EX) or dry static apnea (SA) has not been studied. We examined the hypotheses that, compared with EX and SA, the magnitude of the 1 ) cardiovascular response and 2 ) hematological response to DYN would be greater. Cardiovascular parameters [heart rate (HR), systolic (SBP), diastolic (DBP), and mean arterial (MAP) blood pressure] were continuously collected in 23 ( F = 6 females) moderate and elite freedivers, first during a maximal DYN, then during a time-matched SA and EX on a swimming ergometer in randomized order. Venous blood draws were made before and following each trial. The change in calculated oxygen saturation (DYN: -17 ± 13%, EX: -2 ± 1%, ΔSA: -2 ± 1%; P < 0.05, all comparisons) was greater during DYN compared with EX and SA. During DYN, ΔSBP (DYN: 104 ± 31 mmHg; EX: 38 ± 23 mmHg; and SA: 20 ± 11 mmHg), ΔDBP (DYN: 45 ± 12 mmHg; EX: 14 ± 10 mmHg; and SA: 15 ± 8 mmHg), and ΔMAP (DYN: 65 ± 17 mmHg; EX: 22 ± 13 mmHg; and SA: 16 ± 9 mmHg) were increased compared with EX and SA, while ΔHR was greater during EX (DYN: -24 ± 23 beats/min; EX: 33 ± 13 beats/min; and SA: -1 ± 10 beats/min) than either DYN or SA ( P < 0.0001, all comparisons). Females had a greater pressor response to EX (ΔSBP: 59 ± 30 mmHg; ΔDBP: 24 ± 14 mmHg; and ΔMAP: 35 ± 8 mmHg) than males (ΔSBP: 31 ± 15 mmHg; ΔDBP: 11 ± 6 mmHg; and ΔMAP: 18 ± 8 mmHg; P < 0.01, all comparisons). Together, these data indicate that DYN elicits a distinct, exaggerated cardiovascular response compared with EX or SA alone. NEW & NOTEWORTHY This study performed a dry dynamic apnea with sport-specific equipment to closely mimic the physiological demands of competition diving. We found the cardiovascular and hematological responses to dynamic apnea were more robust compared with time-matched exercise and dry static apnea control trials. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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