HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Dufour, S. P. Articles by Lonsdorfer, J. Search for Related Content PubMed PubMed Citation Articles by Dufour, S. P. Articles by Lonsdorfer, J.

Exercise training in normobaric hypoxia in endurance runners. I. Improvement in aerobic performance capacity

¹Département de Physiologie et des Explorations Fonctionnelles, Hôpital Civil, and Faculté de Médicine, Institut de Physiologie, Unité Propre de Recherche de l'Enseignement Supérieur Équipe d'Accueil 3072, Strasbourg, France; ²Institute of Anatomy, University of Bern, Bern, Switzerland; ³Laboratoire d'Etudes Physiologiques à l'Exercice, Département des Sciences du Sport et de l'Exercice, Équipe d'Accueil 3872, Université d'Evry Val d'Essonne, Evry, France; and ⁴Service de Cardiologie, Hôpitaux Civils de Colmar, Colmar, France

Submitted 22 June 2005 ; accepted in final form 27 July 2005

This study investigates whether a 6-wk intermittent hypoxia training (IHT), designed to avoid reductions in training loads and intensities, improves the endurance performance capacity of competitive distance runners. Eighteen athletes were randomly assigned to train in normoxia [Nor group; n = 9; maximal oxygen uptake (O_{2 max}) = 61.5 ± 1.1 ml·kg^–1·min^–1] or intermittently in hypoxia (Hyp group; n = 9; O_{2 max} = 64.2 ± 1.2 ml·kg^–1·min^–1). Into their usual normoxic training schedule, athletes included two weekly high-intensity (second ventilatory threshold) and moderate-duration (24–40 min) training sessions, performed either in normoxia [inspired O₂ fraction (FI_O2) = 20.9%] or in normobaric hypoxia (FI_O2 = 14.5%). Before and after training, all athletes realized 1) a normoxic and hypoxic incremental test to determine O_{2 max} and ventilatory thresholds (first and second ventilatory threshold), and 2) an all-out test at the pretraining minimal velocity eliciting O_{2 max} to determine their time to exhaustion (T_lim) and the parameters of O₂ uptake (O₂) kinetics. Only the Hyp group significantly improved O_{2 max} (+5% at both FI_O2, P < 0.05), without changes in blood O₂-carrying capacity. Moreover, T_lim lengthened in the Hyp group only (+35%, P < 0.001), without significant modifications of O₂ kinetics. Despite similar training load, the Nor group displayed no such improvements, with unchanged O_{2 max} (+1%, nonsignificant), T_lim (+10%, nonsignificant), and O₂ kinetics. In addition, T_lim improvements in the Hyp group were not correlated with concomitant modifications of other parameters, including O_{2 max} or O₂ kinetics. The present IHT model, involving specific high-intensity and moderate-duration hypoxic sessions, may potentialize the metabolic stimuli of training in already trained athletes and elicit peripheral muscle adaptations, resulting in increased endurance performance capacity.

maximal oxygen uptake; time to exhaustion; competitive endurance runners

This article has been cited by other articles:

				M. Neya, T. Enoki, Y. Kumai, T. Sugoh, and T. Kawahara The effects of nightly normobaric hypoxia and high intensity training under intermittent normobaric hypoxia on running economy and hemoglobin mass J Appl Physiol, September 1, 2007; 103(3): 828 - 834. [Abstract] [Full Text] [PDF]

				J. Padilla, S. A. Hamilton, E. A. Lundgren, J. M. McKenzie, and T. D. Mickleborough Exercise training in normobaric hypoxia: is carbonic anhydrase III the best marker of hypoxia? J Appl Physiol, August 1, 2007; 103(2): 730 - 730. [Full Text] [PDF]

				E A Hinckson, M J Hamlin, M R Wood, and W G Hopkins Game performance and intermittent hypoxic training Br. J. Sports Med., August 1, 2007; 41(8): 537 - 539. [Abstract] [Full Text] [PDF]

				J. Zoll, E. Ponsot, S. Dufour, S. Doutreleau, R. Ventura-Clapier, M. Vogt, H. Hoppeler, R. Richard, and M. Fluck Exercise training in normobaric hypoxia in endurance runners. III. Muscular adjustments of selected gene transcripts J Appl Physiol, April 1, 2006; 100(4): 1258 - 1266. [Abstract] [Full Text] [PDF]

				E. Ponsot, S. P. Dufour, J. Zoll, S. Doutrelau, B. N'Guessan, B. Geny, H. Hoppeler, E. Lampert, B. Mettauer, R. Ventura-Clapier, et al. Exercise training in normobaric hypoxia in endurance runners. II. Improvement of mitochondrial properties in skeletal muscle J Appl Physiol, April 1, 2006; 100(4): 1249 - 1257. [Abstract] [Full Text] [PDF]