Biomedical Science and Engineering
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Biomedical Science and Engineering. 2016, 4(2), 31-36
DOI: 10.12691/bse-4-2-1
Open AccessArticle

Significance of Bilateral Coactivation Ratio for Analysis of Neuromuscular Fatigue of Selected Knee Extensor Muscles during Isometric Contractions at 0º in Sportspersons

Sanjeev Nara1, Manvinder Kaur1, Dhananjoy Shaw2 and Dinesh Bhatia3,

1Department of Biomedical Engineering, Deenbandhu Chhotu Ram University of Science & Technology, Haryana, India

2Indira Gandhi Institute of Physical Education and Sports Sciences, University of Delhi, Delhi, India

3Biomedical Engineering Department, North Eastern Hill University Shillong, India

Pub. Date: October 28, 2016

Cite this paper:
Sanjeev Nara, Manvinder Kaur, Dhananjoy Shaw and Dinesh Bhatia. Significance of Bilateral Coactivation Ratio for Analysis of Neuromuscular Fatigue of Selected Knee Extensor Muscles during Isometric Contractions at 0º in Sportspersons. Biomedical Science and Engineering. 2016; 4(2):31-36. doi: 10.12691/bse-4-2-1


Muscle coactivation is the activation of two or more muscles simultaneously around a joint. Coactivation of knee muscles especially quadriceps is considered to be an important phenomenon for the stabilization of patellofemoral joint. The purpose of this study was to investigate the Coactivation ratio of selected knee extensor muscles as measure of neuromuscular fatigue in relation to gender, performance and side (right and left) of male (n1=19) and female (n2=8) during isometric contraction. The isometric contraction consisted of performing knee extension with an angle between 0º to 10º with a load of 30 repetition maximum (RM) on the CYBEX exerciser. The statistical analysis applied were ANOVA with post hoc analysis to determine the influence of fatigue in terms of gender, performance and side (right and left). The results showed significant decrease in the coactivation ratio of the selected muscles pair during isometric contraction with progression of fatigue (time). It also showed male dominance behavior over females in coactivation of Vastus Medialis (VM) and Vastus Lateralis (VL) muscles.. The results of this study would help to better understand the changes in activation strategies that can provide valuable information regarding the mechanisms that alter neuromuscular activity.

coactivation ratio fatigue gender isometric bilateral

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