Oxygenation and EMG in the proximal and distal vastus lateralis muscle during submaximal isometric knee extension
2010 (English) In: Journal of Sports Sciences, ISSN 0264-0414, E-ISSN 1466-447X, Vol. 28, no 10, p. 1057-1064Article in journal (Refereed) Published
Abstract [en]
Muscle oxygenation responses are reportedly greater in the distal muscle region than in the proximal muscle region. We combined near infrared spectroscopy and electromyography (EMG) to determine whether regional differences in oxygenation are associated with differences in (1) muscle activation and/or (2) fatigue development. Nine males performed 2-min sustained isometric knee extensions at 15% and 30% maximum voluntary contraction during which oxygenation and EMG were recorded simultaneously from proximal and distal locations of the vastus lateralis muscle. Near infrared spectroscopy variables for oxygen saturation (StO2%) were initial slope at contraction onset, peak drop, and recovery slope at contraction end. Electromyography produced the root mean square to indicate muscle activation and mean power frequency changes over time (decreasing slope) to indicate fatigue development. For StO2%, significantly greater peak drop and steeper recovery slope were found for the distal muscle region than for the proximal muscle region. Root mean square, however, was not different between locations. Mean power frequency decreased throughout the contractions but changes were not different between locations. Our results indicate that for modest submaximal contractions, regional differences in oxygenation are not associated with differences in muscle activation or with fatigue development (as interpreted by changes in mean power frequency over time).
Place, publisher, year, edition, pages 2010. Vol. 28, no 10, p. 1057-1064
Keywords [en]
Near infrared spectroscopy, electromyography, isometric contraction, proximal, distal
National Category
Occupational Health and Environmental Health
Identifiers URN: urn:nbn:se:hig:diva-7349 DOI: 10.1080/02640414.2010.489195 ISI: 000281032000005 PubMedID: 20686998 Scopus ID: 2-s2.0-77955724872 OAI: oai:DiVA.org:hig-7349 DiVA, id: diva2:343788
2010-08-162010-08-162025-10-02 Bibliographically approved