Document Detail


Effects of intermittent hypoxia on heart rate variability during rest and exercise.
MedLine Citation:
PMID:  16185139     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Changes in heart rate variability induced by an intermittent exposure to hypoxia were evaluated in athletes unacclimatized to altitude. Twenty national elite athletes trained for 13 days at 1200 m and either lived and slept at 1200 m (live low, train low, LLTL) or between 2500 and 3000 m (live high, train low, LHTL). Subjects were investigated at 1200 m prior to and at the end of the 13-day training camp. Exposure to acute hypoxia (11.5% O(2)) during exercise resulted in a significant decrease in spectral components of heart rate variability in comparison with exercise in normoxia: total power (p < 0.001), low-frequency component. LF (p < 0.001), high-frequency component, HF (p < 0.05). Following acclimatization, the LHTL group increased its LF component (p < 0.01) and LF/HF ratio during exercise in hypoxia after the training period. In parallel, exposure to intermittent hypoxia caused an increased ventilatory response to hypoxia. Acclimatization modified the correlation between the ventilatory response to hypoxia at rest and the difference in total power between normoxia and hypoxia (r (2) = 0.65, p < 0.001). The increase in total power, LF component, and LF/HF ratio suggests that intermittent hypoxic training increased the response of the autonomic nervous system mainly through increased sympathetic activity.
Authors:
Camilo Povea; Laurent Schmitt; Julien Brugniaux; Gérard Nicolet; Jean-Paul Richalet; Jean-Pierre Fouillot
Related Documents :
8929579 - Eucapnic hypoxia lowers human cold thermoregulatory response thresholds and accelerates...
19417229 - Cycling performance following adaptation to two protocols of acutely intermittent hypoxia.
2450729 - Quantitative eeg changes due to hypobaric hypoxia in normal subjects.
1906629 - The effects of catecholamines on ventilation in rainbow trout during hypoxia or hyperca...
2496079 - Changes in breath 13co2/12co2 consequent to exercise and hypoxia.
20701769 - Effect of acute hypoxia on respiratory muscle fatigue in healthy humans.
1549019 - The accuracy of the acsm cycle ergometry equation.
378729 - Comparison of clinical effects of propranolol (inderal) with once daily slow-release ox...
24202049 - Factors affecting the myocardial activity acquired during exercise spect with a high-se...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  High altitude medicine & biology     Volume:  6     ISSN:  1527-0297     ISO Abbreviation:  High Alt. Med. Biol.     Publication Date:  2005  
Date Detail:
Created Date:  2005-09-27     Completed Date:  2005-12-16     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  100901183     Medline TA:  High Alt Med Biol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  215-25     Citation Subset:  IM; S    
Affiliation:
Université Paris 13, Faculté de Médecine, Bobigny, France.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acclimatization / physiology*
Adaptation, Physiological / physiology*
Adult
Anoxia*
Autonomic Nervous System / physiology
Exercise / physiology*
Heart Rate / physiology*
Humans
Male
Oxygen Consumption / physiology
Pulmonary Ventilation / physiology
Reference Values
Rest / physiology*
Running
Swimming

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  The maximum expiratory flow-volume loop in natives of Ladakh and acclimatized lowlanders.
Next Document:  A survey of emergency medical services in mountain areas of Europe and North America: official recom...