Document Detail

Natural goal-directed movements and the triphasic EMG.
MedLine Citation:
PMID:  10529501     Owner:  NLM     Status:  MEDLINE    
Triphasic electromyographic (EMG) patterns have been described as characteristic of rapid, discrete, uniplanar, goal-directed movements. This experiment examined the effects of Response Type (experimenter- vs. subject-determined), Hand (preferred vs. nonpreferred), and Practice (early vs. late) on performance accuracy, and specific temporal EMG and kinematic measures during a dart throw. EMG was recorded from triceps (main agonist), brachioradialis, and biceps (main antagonist). The number of trials in which a triphasic EMG occurred varied systematically across conditions. The experimenter-determined, early practice condition resulted in greatest frequency (92%) of trials displaying a triphasic EMG and least accurate performance. In contrast, the lowest frequency (79%) of triphasic EMG and most accurate performance occurred in the subject-determined, late practice condition. The association among 14 temporal EMG, and kinematic measures for each trial of the dart throw was analyzed with multivariate factorial ANOVA. Four clusters of variables emerged: initial phase, braking phase, terminal phase, and movement speed and duration. Variables contributing to the initial-phase cluster were most strongly associated within the experimenter-determined, early practice condition, and the strength of association was directly related to diminished performance accuracy. Paradoxically, best performance accuracy (subject-determined, late practice) was identified with a weaker association among variables representing the initial phase.
S Morrison; J G Anson
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Motor control     Volume:  3     ISSN:  1087-1640     ISO Abbreviation:  Motor Control     Publication Date:  1999 Oct 
Date Detail:
Created Date:  2000-03-09     Completed Date:  2000-03-09     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  9706297     Medline TA:  Motor Control     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  346-71     Citation Subset:  IM    
School of Physiotherapy and Exercise Science, Griffith University, Gold Coast Campus, Queensland 9276, Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Analysis of Variance
Arm / physiology*
Factor Analysis, Statistical
Functional Laterality / physiology
Muscle, Skeletal / physiology*
Practice (Psychology)
Psychomotor Performance / physiology*
Reaction Time / physiology
Time Factors
Time and Motion Studies
Volition / physiology*

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

Previous Document:  Determination of the maximum steady state of lactate (MLSS) in saliva: an alternative to blood lacta...
Next Document:  Spontaneous and intentional pattern switching in a multisegmental bimanual coordination task.