{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T02:46:20Z","timestamp":1773456380976,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T00:00:00Z","timestamp":1625011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2020R1A2C1011889"],"award-info":[{"award-number":["NRF-2020R1A2C1011889"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Infrared thermal imaging has been widely used to show the correlation between thermal characteristics of the body and muscle activation. This study aims to investigate a method using thermal imaging to visualize and differentiate target muscles during resistance training. Thermal images were acquired to monitor three target muscles (i.e., biceps brachii, triceps brachii, and deltoid muscle) in the brachium while varying the training weight, duration, and order of training. The acquired thermal images were segmented and converted to heat maps. By generating difference heat maps from pairs of heat maps during training, the target muscles were clearly visualized, with an average temperature difference of 0.86 \u00b0C. It was observed that training order had no significant effect on skin surface temperature. The difference heat maps were also used to train a convolutional neural network (CNN) to show the feasibility of target muscle classification, with an accuracy of 92.3%. This study demonstrated that infrared thermal imaging could be effectively utilized to locate and differentiate target muscle activation during resistance training.<\/jats:p>","DOI":"10.3390\/s21134505","type":"journal-article","created":{"date-parts":[[2021,7,1]],"date-time":"2021-07-01T02:44:39Z","timestamp":1625107479000},"page":"4505","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Detection of Muscle Activation during Resistance Training Using Infrared Thermal Imaging"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5441-1663","authenticated-orcid":false,"given":"Haemin","family":"Jung","sequence":"first","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"}]},{"given":"Jeongwung","family":"Seo","sequence":"additional","affiliation":[{"name":"School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 06974, Korea"}]},{"given":"Kangwon","family":"Seo","sequence":"additional","affiliation":[{"name":"School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 06974, Korea"}]},{"given":"Dohwi","family":"Kim","sequence":"additional","affiliation":[{"name":"Thermoeye, Seoul 06979, Korea"}]},{"given":"Suhyun","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"687","DOI":"10.1007\/s40279-015-0454-0","article-title":"Training Monitoring for Resistance Exercise: Theory and Applications","volume":"46","author":"Scott","year":"2016","journal-title":"Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5606","DOI":"10.1038\/s41598-017-05953-2","article-title":"A comparison of traditional and novel metrics to quantify resistance training","volume":"7","author":"Marston","year":"2017","journal-title":"Sci. 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