{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T03:59:23Z","timestamp":1780977563948,"version":"3.54.1"},"reference-count":28,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,14]],"date-time":"2022-06-14T00:00:00Z","timestamp":1655164800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Zuoying Branch of Kaohsiung Armed Forces General Hospital","award":["KAFGH-ZY-A-110023"],"award-info":[{"award-number":["KAFGH-ZY-A-110023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The plank is a common core-stability exercise. Developing a wearable inertial sensor system for distinguishing between acceptable and aberrant plank techniques and detecting specific deviations from acceptable plank techniques can enhance performance and prevent injury. The purpose of this study was to develop an inertial measurement unit (IMU)-based plank technique quantification system. Nineteen healthy volunteers (age: 20.5 \u00b1 0.8 years, BMI: 22.9 \u00b1 1.4 kg\/m2) performed the standard plank technique and six deviations with five IMUs positioned on the occiput, cervical spine, thoracic spine, sacrum, and right radius to record movements. The random forest method was employed to perform the classification. The proposed binary tree classification model achieved an accuracy of more than 86%. The average sensitivities were higher than 90%, and the specificities were higher than 91%, except for one deviation (83%). These results suggest that the five IMU-based systems can classify the plank technique as acceptable or aberrant with good accuracy, high sensitivity, and acceptable specificity, which has significant implications in monitoring plank biomechanics and enabling coaching practice.<\/jats:p>","DOI":"10.3390\/s22124510","type":"journal-article","created":{"date-parts":[[2022,6,15]],"date-time":"2022-06-15T01:39:54Z","timestamp":1655257194000},"page":"4510","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Classification of Plank Techniques Using Wearable Sensors"],"prefix":"10.3390","volume":"22","author":[{"given":"Zong-Rong","family":"Chen","sequence":"first","affiliation":[{"name":"Department of Athletic Performance, National University of Kaohsiung, Kaohsiung 811, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei-Chi","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Education and Sport Sciences, College of Sports and Recreation, National Taiwan Normal University, Taipei 106, Taiwan"},{"name":"Division of Physical Medicine and Rehabilitation, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung 813, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shih-Feng","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Applied Mathematics, National University of Kaohsiung, Kaohsiung 811, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tzu-Yi","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Statistics, National University of Kaohsiung, Kaohsiung 811, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9962-0506","authenticated-orcid":false,"given":"Chen-Yi","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Long-Term Care, National Taipei University of Nursing and Health Sciences, Taipei 112, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Adesida, Y., Papi, E., and McGregor, A.H. 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