Training in hypoxia fails to further enhance endurance performance and lactate clearance in well-trained men and impairs glucose metabolism during prolonged exercise.
Détails
Etat: Public
Version: Final published version
ID Serval
serval:BIB_B740EAEE876F
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Training in hypoxia fails to further enhance endurance performance and lactate clearance in well-trained men and impairs glucose metabolism during prolonged exercise.
Périodique
Experimental Physiology
ISSN
1469-445X (Electronic)
ISSN-L
0958-0670
Statut éditorial
Publié
Date de publication
2010
Peer-reviewed
Oui
Volume
95
Numéro
2
Pages
315-330
Langue
anglais
Résumé
The aim of this study was to investigate the synergistic effects of endurance training and hypoxia on endurance performance in normoxic and hypoxic conditions (approximately 3000 m above sea level) as well as on lactate and glucose metabolism during prolonged exercise. For this purpose, 14 well-trained cyclists performed 12 training sessions in conditions of normobaric hypoxia (HYP group, n = 7) or normoxia (NOR group, n = 7) over 4 weeks. Before and after training, lactate and glucose turnover rates were measured by infusion of exogenous lactate and stable isotope tracers. Endurance performance was assessed during incremental tests performed in normoxia and hypoxia and a 40 km time trial performed in normoxia. After training, performance was similarly and significantly improved in the NOR and HYP groups (training, P < 0.001) in normoxic conditions. No further effect of hypoxic training was found on markers of endurance performance in hypoxia (training x hypoxia interaction, n.s.). In addition, training and hypoxia had no significant effect on lactate turnover rate. In contrast, there was a significant interaction of training and hypoxia (P < 0.05) on glucose metabolism, as follows: plasma insulin and glucose concentrations were significantly increased; glucose metabolic clearance rate was decreased; and the insulin to glucagon ratio was increased after training in the HYP group. In conclusion, our results show that, compared with training in normoxia, training in hypoxia has no further effect on endurance performance in both normoxic and hypoxic conditions or on lactate metabolic clearance rate. Additionally, these findings suggest that training in hypoxia impairs blood glucose regulation in endurance-trained subjects during exercise.
Mots-clé
Adult, Altitude, Anoxia/physiopathology, Blood Glucose/metabolism, Exercise Tolerance, Humans, Lactic Acid/blood, Male, Metabolic Clearance Rate, Physical Exertion, Physical Fitness, Task Performance and Analysis
Pubmed
Web of science
Open Access
Oui
Création de la notice
10/03/2010 11:39
Dernière modification de la notice
20/08/2019 16:25