{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,8]],"date-time":"2026-08-08T18:22:06Z","timestamp":1786213326670,"version":"3.56.0"},"reference-count":32,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,1,29]],"date-time":"2019-01-29T00:00:00Z","timestamp":1548720000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31771069"],"award-info":[{"award-number":["31771069"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31800824"],"award-info":[{"award-number":["31800824"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005230","name":"Natural Science Foundation of Chongqing","doi-asserted-by":"publisher","award":["cstc2018jcyjAX0390"],"award-info":[{"award-number":["cstc2018jcyjAX0390"]}],"id":[{"id":"10.13039\/501100005230","id-type":"DOI","asserted-by":"publisher"}]},{"name":"graduate research and innovation foundation of Chongqing, China","award":["CYB17038"],"award-info":[{"award-number":["CYB17038"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The study aims to explore the spatial distribution of multi-tendinous muscle modulated by central nervous system (CNS) during sustained contraction. Nine subjects were recruited to trace constant target forces with right index finger extension. Surface electromyography (sEMG) of extensor digitorum (ED) were recorded with a 32-channel electrode array. Nine successive topographic maps (TM) were obtained. Pixel wise analysis was utilized to extract subtracted topographic maps (STM), which exhibited inhomogeneous distribution. STMs were characterized into hot, warm, and cool regions corresponding to higher, moderate, and lower change ranges, respectively. The relative normalized area (normalized to the first phase) of these regions demonstrated different changing trends as rising, plateauing, and falling over time, respectively. Moreover, the duration of these trends were found to be affected by force level. The rising\/falling periods were longer at lower force levels, while the plateau can be achieved from the initial phase for higher force output (45% maximal voluntary contraction). The results suggested muscle activity reorganization in ED plays a role to maintain sustained contraction. Furthermore, the decreased dynamical regulation ability to spatial reorganization may be prone to induce fatigue. This finding implied that spatial reorganization of muscle activity as a regulation mechanism contribute to maintain constant force production.<\/jats:p>","DOI":"10.3390\/s19030555","type":"journal-article","created":{"date-parts":[[2019,1,29]],"date-time":"2019-01-29T11:27:52Z","timestamp":1548761272000},"page":"555","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Spatial Reorganization of Myoelectric Activities in Extensor Digitorum for Sustained Finger Force Production"],"prefix":"10.3390","volume":"19","author":[{"given":"Zhixian","family":"Gao","sequence":"first","affiliation":[{"name":"Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China"},{"name":"Chongqing Engineering Research Center of Medical Electronics Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shangjie","family":"Tang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China"},{"name":"Chongqing Engineering Research Center of Medical Electronics Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoying","family":"Wu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China"},{"name":"Chongqing Key Laboratory of Artificial Intelligence and Service Robot Control Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiang","family":"Fu","sequence":"additional","affiliation":[{"name":"College of Automation, Harbin Engineering University, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingyu","family":"Fan","sequence":"additional","affiliation":[{"name":"Chongqing Engineering Research Center of Medical Electronics Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yun","family":"Zhao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China"},{"name":"Chongqing Engineering Research Center of Medical Electronics Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lintao","family":"Hu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China"},{"name":"Chongqing Key Laboratory of Artificial Intelligence and Service Robot Control Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Chen","sequence":"additional","affiliation":[{"name":"Chongqing Engineering Research Center of Medical Electronics Technology, Chongqing 400044, China"},{"name":"Chongqing Key Laboratory of Artificial Intelligence and Service Robot Control Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wensheng","family":"Hou","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China"},{"name":"Chongqing Engineering Research Center of Medical Electronics Technology, Chongqing 400044, China"},{"name":"Chongqing Key Laboratory of Artificial Intelligence and Service Robot Control Technology, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1532","DOI":"10.1097\/00005768-199612000-00016","article-title":"Skeletal Muscle: Form and Function","volume":"28","author":"Antonio","year":"1996","journal-title":"Med. 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