Document Detail


Reduced heterogeneity of muscle deoxygenation during heavy bicycle exercise.
MedLine Citation:
PMID:  15741839     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
PURPOSE: This study evaluated heterogeneity of muscle O2 dynamics in a single muscle during bicycle exercise using an eight-channel near-infrared continuous wave spectroscopy (NIRcws) mapping system. METHODS: Nine healthy subjects performed bicycle exercise at fixed workloads of 20, 40, 60, 80, and 100% maximal workload for 5 min at each level. Muscle oxygenation in the vastus lateralis (VL) during and after each exercise was monitored using the NIRcws mapping system. Pulmonary O2 uptake and heart rate were monitored continuously during the experiment. Blood samples were taken to measure blood lactate concentration at 30 s after each exercise stage. RESULTS: Half time reoxygenation, the time taken to reach a value of half-maximal recovery, was significantly delayed in distal sites compared with proximal sites of VL. Conversely, muscle deoxygenation for all measurement sites increased incrementally with higher exercise workloads, and no significant difference of deoxygenation level showed within each channel. However, relative dispersion of muscle deoxygenation during exercise significantly decreased when the workload increased. Moreover, relative dispersion of muscle deoxygenation between the subjects also decreased with an increase in the workload. CONCLUSION: Muscle deoxygenation in a single muscle was more heterogeneous at lower exercise workloads, and variations of the muscle deoxygenation heterogeneity between subjects were greater at lower exercise workloads.
Authors:
Ryotaro Kime; Joohee Im; Daniel Moser; Yuanqing Lin; Shoko Nioka; Toshihito Katsumura; Britton Chance
Related Documents :
18936219 - Coingestion of carbohydrate and protein hydrolysate stimulates muscle protein synthesis...
6700629 - Changes in fiber type composition in growing muscle as a result of dynamic exercise and...
12067859 - Effects of endurance training on activity and expression of amp-activated protein kinas...
8790589 - Regional changes in capillary supply in skeletal muscle of interval-sprint and low-inte...
19359609 - Ampk activation is fiber type specific in human skeletal muscle: effects of exercise an...
12153959 - Adaptation of upper airway muscles to chronic endurance exercise.
17711199 - Characterization of the polarity of natural organic matter under ambient conditions by ...
17720799 - Post-mortem evidence of idiopathic left ventricular hypertrophy and idiopathic intersti...
8214949 - Exercise-induced refractoriness in asthmatic subjects involves leukotriene and prostagl...
Publication Detail:
Type:  Clinical Trial; Comparative Study; Journal Article    
Journal Detail:
Title:  Medicine and science in sports and exercise     Volume:  37     ISSN:  0195-9131     ISO Abbreviation:  Med Sci Sports Exerc     Publication Date:  2005 Mar 
Date Detail:
Created Date:  2005-03-02     Completed Date:  2005-05-18     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8005433     Medline TA:  Med Sci Sports Exerc     Country:  United States    
Other Details:
Languages:  eng     Pagination:  412-7     Citation Subset:  IM; S    
Affiliation:
Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA. kime@tokyo-med.ac.jp
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Bicycling / physiology*
Exercise / physiology*
Female
Heart Rate / physiology
Humans
Male
Muscle, Skeletal / metabolism*
Oxygen / metabolism*
Oxygen Consumption / physiology
Task Performance and Analysis
Chemical
Reg. No./Substance:
7782-44-7/Oxygen

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


Previous Document:  Failure to repeatedly supercompensate muscle glycogen stores in highly trained men.
Next Document:  The chemoreflex: adult versus child comparison.