Document Detail


The effects of training on the metabolic and respiratory profile of high-intensity cycle ergometer exercise.
MedLine Citation:
PMID:  2303047     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The tolerable work duration (t) for high-intensity cycling is well described as a hyperbolic function of power (W): W = (W'.t-1) + Wa, where Wa is the upper limit for sustainable power (lying between maximum W and the threshold for sustained blood [lactate] increase, theta lac), and W' is a constant which defines the amount of work which can be performed greater than Wa. As training increases the tolerable duration of high-intensity cycling, we explored whether this reflected an alteration of Wa, W' or both. Before and after a 7-week regimen of intense interval cycle-training by healthy males, we estimated ( ) theta lac and determined maximum O2 uptake (mu VO2); Wa; W'; and the temporal profiles of pulmonary gas exchange, blood gas, acid-base and metabolic response to constant-load cycling at and above Wa. Although training increased theta lac (24%), mu VO2 (15%) and Wa (15%), W' was unaffected. For exercise at Wa, a steady state was attained for VO2, [lactate] and pH both pre- and post-training, despite blood [norepinephrine] and [epinephrine] ([NE], [E]) and rectal temperature continuing to rise. For exercise greater than Wa, there was a progressive increase in VO2 (resulting in mu VO2 at fatigue), [lactate], [NE], [E] and rectal temperature, and a progressive decrease for pH. We conclude that the increased endurance capacity for high-intensity exercise following training reflects an increased W asymptote of the W-t relationship with no effect on its curvature; consequently, there is no appreciable change in the amount of work which can be performed above Wa.(ABSTRACT TRUNCATED AT 250 WORDS)
Authors:
D C Poole; S A Ward; B J Whipp
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  European journal of applied physiology and occupational physiology     Volume:  59     ISSN:  0301-5548     ISO Abbreviation:  Eur J Appl Physiol Occup Physiol     Publication Date:  1990  
Date Detail:
Created Date:  1990-03-22     Completed Date:  1990-03-22     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0410266     Medline TA:  Eur J Appl Physiol Occup Physiol     Country:  GERMANY, WEST    
Other Details:
Languages:  eng     Pagination:  421-9     Citation Subset:  IM; S    
Affiliation:
Department of Anesthesiology, UCLA 90024.
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MeSH Terms
Descriptor/Qualifier:
Adult
Exercise / physiology*
Humans
Lactates / metabolism*
Male
Oxygen Consumption / physiology*
Physical Education and Training*
Pulmonary Gas Exchange / physiology*
Grant Support
ID/Acronym/Agency:
HL 07694/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Lactates

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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