Maximal lactic capacity at altitude: effect of bicarbonate loading.

Détails

ID Serval
serval:BIB_28F3D7FE6013
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Maximal lactic capacity at altitude: effect of bicarbonate loading.
Périodique
Journal of Applied Physiology
Auteur(s)
Kayser B., Ferretti G., Grassi B., Binzoni T., Cerretelli P.
ISSN
8750-7587 (Print)
ISSN-L
0161-7567
Statut éditorial
Publié
Date de publication
1993
Volume
75
Numéro
3
Pages
1070-1074
Langue
anglais
Résumé
The aim of the present study was to test the hypothesis that the net maximal blood lactate accumulation ([La]max) during heavy exercise in lowlanders acclimatized to chronic hypoxia may be limited by the reduced bicarbonate stores. Six men [age 32 +/- 4 (SD) yr] performed supramaximal exercise until voluntary exhaustion at sea level (204 +/- 54 W) and after sojourning for 1 mo at 5,050 m (175 +/- 23 W), without (C) and with (B) oral sodium-bicarbonate loading (0.3 g/kg body wt). Exhaustion time, arterial blood lactate concentration, arterial pH (pHa), arterial PCO2, and intramuscular pH were measured at rest and after exercise. At sea level, exhaustion time increased from 6.5 +/- 2.8 min in C to 7.5 +/- 2.7 min in B (P < 0.05). At altitude, exhaustion times were similar to the sea level C values and the same in C and B. At sea level, resting pHa increased from 7.41 +/- 0.02 in C to 7.46 +/- 0.03 in B (P < 0.001); the corresponding values at altitude were 7.46 +/- 0.04 and 7.55 +/- 0.03 (P < 0.001). Postexercise pHa at sea level was 7.22 +/- 0.02 in C and 7.25 +/- 0.08 in B (NS). After exercise at altitude, pHa was 7.32 +/- 0.04 and 7.44 +/- 0.03 in C and B, respectively (P < 0.001). [La]max increased from 12.86 +/- 1.45 mM in C to 16.63 +/- 1.76 mM in B (P < 0.01) at sea level and from 6.85 +/- 1.40 mM in C to 7.95 +/- 1.74 mM in B (NS) at altitude.(ABSTRACT TRUNCATED AT 250 WORDS)
Mots-clé
Acid-Base Equilibrium, Adult, Altitude, Arteries, Humans, Hydrogen-Ion Concentration, Lactates/blood, Lactic Acid, Male, Muscles/metabolism, Physical Endurance, Physical Exertion, Sodium Bicarbonate/pharmacology
Pubmed
Web of science
Création de la notice
19/09/2013 11:24
Dernière modification de la notice
20/08/2019 14:08
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