Linked Life Data

1893907

Source:http://linkedlifedata.com/resource/pubmed/id/1893907

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1991-10-22
pubmed:abstractText
The effect of shortening velocity on the reduction in work output, energy consumption and efficiency during repetitive contractions has been determined in rat extensor digitorum longus muscle. Muscles in situ (with occluded blood flow, 37 degrees C) were stimulated to perform 40 successive contractions (at 4 Hz) with a total duration of the exercise period of 10 s and shortening velocities of either 25, 50 or 75 mm.s-1 (whole muscle-tendon complex). Care was taken that work output during the shortening phase of the first contraction was the same for the different velocities used. Total work output of the 40 contractions was not significantly different between the three groups with different shortening velocities; nor was there a significant difference in the high-energy phosphate consumption over this 10-s exercise period. However, when the ratio of total work output and total energy consumption was calculated a significantly higher efficiency (25-30% in comparison with the efficiency of the other two velocities) was found with the shortening velocity of 50 mm.s-1. There was no significant difference in efficiency between shortening velocities of 25 and 75 mm.s-1. This suggests that with this protocol efficiency showed a velocity-dependent pattern that may have the same shape as the power/velocity curve. Whereas total work output during the 10-s exercise period was not significantly different between the velocities studied, the time course of the changes in work output was quite different. With shortening velocities of 50 and 75 mm.s-1 work output initially increased by maximally 6% and 12% respectively in contrast to a steady level in the contractions with a velocity of 25 mm.s-1.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0301-5548
pubmed:author
pubmed:issnType
Print
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
430-5
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Effect of shortening velocity on work output and energy cost during repeated contractions of the rat EDL muscle.
pubmed:affiliation
Department of Muscle and Exercise Physiology, Faculty of Human Movement Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article