Cardiorespiratory Coordination in Hypercapnic Test Before and After High-Altitude Expedition.

Autor: Gultyaeva VV; Laboratory of Functional Reserves of Human Organism, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia., Uryumtsev DY; Laboratory of Functional Reserves of Human Organism, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia., Zinchenko MI; Laboratory of Functional Reserves of Human Organism, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia., Melnikov VN; Laboratory of Functional Reserves of Human Organism, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia., Balioz NV; Laboratory of Functional Reserves of Human Organism, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia., Krivoschekov SG; Laboratory of Functional Reserves of Human Organism, Scientific Research Institute of Neurosciences and Medicine, Novosibirsk, Russia.
Jazyk: angličtina
Zdroj: Frontiers in physiology [Front Physiol] 2021 May 24; Vol. 12, pp. 673570. Date of Electronic Publication: 2021 May 24 (Print Publication: 2021).
DOI: 10.3389/fphys.2021.673570
Abstrakt: Coordination of cardiovascular and respiratory systems enables a wide range of human adaptation and depends upon the functional state of an individual organism. Hypoxia is known to elicit changes in oxygen and carbon dioxide sensitivity, while training alters cardiorespiratory coordination (CRC). The delayed effect of high altitude (HA) acclimatization on CRC in mountaineers remains unknown. The objective of this study was to compare CRC in acute hypercapnia in mountaineers before and after a HA expedition. Nine trained male mountaineers were investigated at sea level before (Pre-HA) and after a 20-day sojourn at altitudes of 4,000-7,000 m (Post-HA) in three states (Baseline, Hypercapnic Rebreathing, and Recovery). A principal component (PC) analysis was performed to evaluate the CRC. The number of mountaineers with one PC increased Post-HA (nine out of nine), compared to Pre-HA (five out of nine) [Chi-square (df = 1) = 5.14, P = 0.023]; the percentage of total variance explained by PC1 increased [Pre-HA median 65.6 (Q1 64.9/Q3 74.9), Post-HA 75.6 (73.3/77.9), P = 0.028]. Post-HA, the loadings of the expired fraction of O2, CO2, and ventilation onto PC1 did not change, and the loading of heart rate increased [Pre-HA 0.64 (0.45/0.68) and Post-HA 0.76 (0.65/0.82), P = 0.038]. During the Recovery, the percentage of total variance explained by PC1 was higher than during the Baseline. Post-HA, there was a high correlation between the Exercise addiction scores and the eigenvalues of PC1 ( r = 0.9, P = 0.001). Thus, acute hypercapnic exposure reveals the Post-HA increase in cardiorespiratory coordination, which is highly related to the level of exercise addiction.
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2021 Gultyaeva, Uryumtsev, Zinchenko, Melnikov, Balioz and Krivoschekov.)
Databáze: MEDLINE