Maximal lactic capacity at altitude: effect of bicarbonate loading.

Details

Serval ID
serval:BIB_28F3D7FE6013
Type
Article: article from journal or magazin.
Collection
Publications
Title
Maximal lactic capacity at altitude: effect of bicarbonate loading.
Journal
Journal of Applied Physiology
Author(s)
Kayser B., Ferretti G., Grassi B., Binzoni T., Cerretelli P.
ISSN
8750-7587 (Print)
ISSN-L
0161-7567
Publication state
Published
Issued date
1993
Volume
75
Number
3
Pages
1070-1074
Language
english
Abstract
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)
Keywords
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
Create date
19/09/2013 10:24
Last modification date
20/08/2019 13:08
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