Maximal rate of blood lactate accumulation during exercise at altitude in humans.

Détails

ID Serval
serval:BIB_A96132C03134
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Maximal rate of blood lactate accumulation during exercise at altitude in humans.
Périodique
Journal of Applied Physiology
Auteur⸱e⸱s
Grassi B., Ferretti G., Kayser B., Marzorati M., Colombini A., Marconi C., Cerretelli P.
ISSN
8750-7587 (Print)
ISSN-L
0161-7567
Statut éditorial
Publié
Date de publication
1995
Volume
79
Numéro
1
Pages
331-339
Langue
anglais
Résumé
The lower peak lactate accumulation in blood ([La(b)]p) at altitude may be associated with a reduced maximal glycolytic flux. Based on certain assumptions, the latter can be indirectly evaluated in vivo, during short supramaximal exercises, by measuring the maximal rate of lactate accumulation in blood (delta [La(b)]max). delta [La(b)]max was determined on six white subjects at sea level (SL1), after approximately 1 wk (Alt1) and 4 wk (Alt2) of a 35-day sojourn at 5,050 m, and 1 wk after return to sea level (SL2). The subjects performed exercises of increasing duration (5, 15, 25, 35, 45 s or until exhaustion) on a bicycle ergometer at loads = 200% of the individual Wmax. The latter was previously determined in each condition as the greatest work rate that could be sustained for 2-4 min during an incremental exercise. Net [La(b)] accumulation (delta [La(b)]) was measured after each exercise bout. delta [La(b)] resulted to be linearly related to exercise duration. The slopes of the individual delta [La(b)] vs. exercise duration lines were taken as delta [La(b)]max. Exhaustion times were approximately 30-45 s in all conditions. [La(b)]p (in mM) during recovery after the exhaustive load was higher at SL1 (10.22 +/- 1.09; means +/- SD) than at Alt1 (5.08 +/- 0.82), Alt2 (8.13 +/- 2.67), and SL2 (8.18 +/- 1.43). delta [La(b)]max was lower at Alt1 (0.09 +/- 0.02) and at Alt2 (0.17 +/- 0.05) than at SL1 (0.25 +/- 0.05) and SL2 (0.23 +/- 0.06). Both [La(b)]p and delta [La(b)]max increased during acclimatization.(ABSTRACT TRUNCATED AT 250 WORDS)
Mots-clé
Acclimatization, Adult, Altitude, Humans, Lactates/blood, Lactic Acid, Male, Physical Exertion, Time Factors
Pubmed
Web of science
Création de la notice
19/09/2013 10:11
Dernière modification de la notice
20/08/2019 15:13
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