{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T19:25:40Z","timestamp":1774725940060,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2016,4,22]],"date-time":"2016-04-22T00:00:00Z","timestamp":1461283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study assessed changes in electrical impedance myography (EIM) at different levels of isometric muscle contraction as well as during exhaustive exercise at 60% maximum voluntary contraction (MVC) until task failure. The EIM was performed on the biceps brachii muscle of 19 healthy subjects. The results showed that there was a significant difference between the muscle resistance (R) measured during the isometric contraction and when the muscle was completely relaxed. Post hoc analysis shows that the resistance increased at higher contractions (both 60% MVC and MVC), however, there were no significant changes in muscle reactance (X) during the isometric contractions. The resistance also changed during different stages of the fatigue task and there were significant decreases from the beginning of the contraction to task failure as well as between task failure and post fatigue rest. Although our results demonstrated an increase in resistance during isometric contraction, the changes were within 10% of the baseline value. These changes might be related to the modest alterations in muscle architecture during a contraction. The decrease in resistance seen with muscle fatigue may be explained by an accumulation of metabolites in the muscle tissue.<\/jats:p>","DOI":"10.3390\/s16040581","type":"journal-article","created":{"date-parts":[[2016,4,25]],"date-time":"2016-04-25T09:55:00Z","timestamp":1461578100000},"page":"581","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":55,"title":["Localized Electrical Impedance Myography of the Biceps Brachii Muscle during Different Levels of Isometric Contraction and Fatigue"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9340-9061","authenticated-orcid":false,"given":"Le","family":"Li","sequence":"first","affiliation":[{"name":"Department of Rehabilitation Medicine, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China"},{"name":"Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA"}]},{"given":"Henry","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA"}]},{"given":"Xiaoyan","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA"}]},{"given":"Sheng","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA"}]},{"given":"Ping","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston; TIRR Memorial Hermann Research Center, Houston, TX 77030, USA"},{"name":"Guangdong Work Injury Rehabilitation Center, Guangzhou 510440, China"}]}],"member":"1968","published-online":{"date-parts":[[2016,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"936","DOI":"10.1002\/mus.21362","article-title":"Electrical Impedance Myography: Background, Current State, and Future Directions","volume":"40","author":"Rutkove","year":"2009","journal-title":"Muscle Nerve"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"595","DOI":"10.1002\/mus.20626","article-title":"Assessing neuromuscular disease with multifrequency electrical impedance myography","volume":"34","author":"Esper","year":"2006","journal-title":"Muscle Nerve"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"390","DOI":"10.1002\/mus.10048","article-title":"Localized bioimpedance analysis in the evaluation of neuromuscular disease","volume":"25","author":"Rutkove","year":"2002","journal-title":"Muscle Nerve"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"560","DOI":"10.1002\/mus.20981","article-title":"Optimizing measurement of the electrical anisotropy of muscle","volume":"37","author":"Chin","year":"2008","journal-title":"Muscle Nerve"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1269","DOI":"10.1088\/0967-3334\/27\/12\/002","article-title":"Electrical impedance in bovine skeletal muscle as a model for the study of neuromuscular disease","volume":"27","author":"Tarulli","year":"2006","journal-title":"Physiol Meas."},{"key":"ref_6","first-page":"37","article-title":"Electrical impedance alterations in the rat hind limb with unloading","volume":"13","author":"Li","year":"2013","journal-title":"J. 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