The effects of interelectrode distance on electromyographic amplitude and mean power frequency during isokinetic and isometric muscle actions of the biceps brachii

2005 ◽  
Vol 15 (5) ◽  
pp. 482-495 ◽  
Author(s):  
Travis W. Beck ◽  
Terry J. Housh ◽  
Glen O. Johnson ◽  
Joseph P. Weir ◽  
Joel T. Cramer ◽  
...  
2005 ◽  
Vol 21 (1) ◽  
pp. 96-109 ◽  
Author(s):  
Travis W. Beck ◽  
Terry J. Housh ◽  
Glen O. Johnson ◽  
Joseph P. Weir ◽  
Joel T. Cramer ◽  
...  

This study compared the patterns of mechanomyographic (MMG) amplitude and mean power frequency vs. torque relationships in men and women during isometric muscle actions of the biceps brachii. Seven men (mean age 23.9 ± 3.5 yrs) and 8 women (mean 21.0 ± 1.3 yrs) performed submaximal to maximal isometric muscle actions of the dominant forearm flexors. Following determination of the isometric maximum voluntary contraction (MVC), they randomly performed submaximal step muscle actions in 10% increments from 10% to 90% MVC. Polynomial regression analyses indicated that the MMG amplitude vs. isometric torque relationship for the men was best fit with a cubic model (R2= 0.983), where MMG amplitude increased slightly from 10% to 20% MVC, increased rapidly from 20% to 80% MVC, and plateaued from 80% to 100% MVC. For the women, MMG amplitude increased linearly (r2= 0.949) from 10% to 100% MVC. Linear models also provided the best fit for the MMG mean power frequency vs. isometric torque relationship in both the men (r2= 0.813) and women (r2= 0.578). The results demonstrated gender differences in the MMG amplitude vs. isometric torque relationship, but similar torque-related patterns for MMG mean power frequency. These findings suggested that the plateau in MMG amplitude at high levels of isometric torque production for the biceps brachii in the men, but not the women, may have been due to greater isometric torque, muscle stiffness, and/or intramuscular fluid pressure in the men, rather than to differences in motor unit activation strategies for modulating isometric torque production.


2006 ◽  
Vol 151 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Moh H. Malek ◽  
Terry J. Housh ◽  
Jared W. Coburn ◽  
Joseph P. Weir ◽  
Richard J. Schmidt ◽  
...  

2008 ◽  
Vol 171 (1) ◽  
pp. 104-109 ◽  
Author(s):  
Trent J. Herda ◽  
Eric D. Ryan ◽  
Travis W. Beck ◽  
Pablo B. Costa ◽  
Jason M. DeFreitas ◽  
...  

2008 ◽  
Vol 168 (2) ◽  
pp. 293-305 ◽  
Author(s):  
Eric D. Ryan ◽  
Travis W. Beck ◽  
Trent J. Herda ◽  
Michael J. Hartman ◽  
Jeffrey R. Stout ◽  
...  

Author(s):  
Şükrü Okkesim ◽  
Kezban Coşkun

Muscle fatigue produces negative effects in the performance and it may lead to a muscle failure. This problem makes the quantitative grading of muscle fatigue a necessity in ergonomic and physiological research. Moreover, the quantitative grading of muscle fatigue is needed to increase work and sport productivity and prevent several accidents that result from muscle fatigue. Even though there are many studies for this aim, there is no quantitative criterion for the evaluation of muscle fatigue. The main reason is that muscle fatigue is a complex physiological situation that is dependent on several parameters. Our aim in this study is to present a new feature to evaluate muscle fatigue and prove the reliability of the new feature by making correlation analyses between this with other features. For this aim, electromyography and mechanomyography signals were simultaneously recorded from the biceps brachii and triceps brachii muscles during the isometric and isotonic contractions of 60 healthy volunteers (30 females, 30 males). The mean power frequency and median frequency, which are used in the literature, were compared to the frequency ratio change, the new measure; correlations between the frequency ratio change and the mean power frequency and median frequency were analysed. There was a high correlation between the features, and frequency ratio change can be used to quantitatively evaluate muscle fatigue.


2001 ◽  
Vol 33 (5) ◽  
pp. S333
Author(s):  
J T. Cramer ◽  
T J. Housh ◽  
J P. Weir ◽  
K T. Ebersole ◽  
G O. Johnson ◽  
...  

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