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Published on: September 13, 2015
Electromyographic signal and force comparisons during maximal voluntary isometric contraction in water and on dry
Stephanie Santana Pinto1, Giane Veiga Liedtke, Cristine Lima Alberton
1Research Group in Water and on Dry Land Activities, School of Physical Education at the Federal University of Rio Grande do Sul, Exercise Research Laboratory, room 208, Felizardo Street, Jardim Botânico, Porto Alegre, RS, Brazil. tetisantana@yahoo.com.br
Abstract:
This study was designed to compare surface electromyographic (sEMG) signal and force production during maximal voluntary isometric contractions (MVCs) in water and on dry land. The reproducibility of sEMG and isometric force measurements between water and dry land environments was also assessed. Nine women performed MVC for elbow flexion and extension, hip flexion, and extension against identical fixed resistance in both environments. The sEMG signal from biceps brachii, triceps brachii, rectus femoris, and biceps femoris was recorded with waterproof adhesives placed over each electrode. The sEMG and force production showed no significant difference between water and dry land, except for HEX (p = 0.035). In addition, intraclass correlation coefficient values were significant and ranged from moderate to high (0.66-0.96) for sEMG and force production between environments. These results showed that the environment did not influence the sEMG and force in MVC.
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