{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T02:45:29Z","timestamp":1770173129123,"version":"3.49.0"},"reference-count":55,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T00:00:00Z","timestamp":1769990400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Tianjin Flying Pigeon Bicycle Co., Ltd.","award":["2023GKF-0416"],"award-info":[{"award-number":["2023GKF-0416"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The kneeling chair has an advantage over the traditional chair in that it promotes lumbar lordosis, while findings regarding muscle activity and subjective (dis)comfort evaluation between the two are inconsistent. Furthermore, there is a lack of studies focusing on the angle combinations of the kneeling chair. This study investigated an unsupported traditional sitting configuration and four unsupported kneeling configurations with different angle combinations through measurements of surface electromyography (EMG) signals, body part discomfort (BPD) scores, and seat configuration evaluation scores. A significant decrease in lumbar erector spinae (LES) muscle activity and perceived discomfort was observed in the kneeling configuration compared with the results for the traditional sitting configuration. Among the four angle combinations, the optimal arrangement was identified, which resulted in significantly less LES muscle activity and perceived discomfort. Our findings provide guidance for the design and future studies of the kneeling chair.<\/jats:p>","DOI":"10.3390\/s26030970","type":"journal-article","created":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T12:46:11Z","timestamp":1770122771000},"page":"970","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessment of the Effect of Four Kneeling Chair Angle Combinations on Muscle Activity and Perceived Discomfort"],"prefix":"10.3390","volume":"26","author":[{"given":"Xiaoxiao","family":"Lei","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering, Tianjin University, Tianjin 300354, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jutao","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education, Tianjin University, Tianjin 300354, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingchen","family":"Cong","sequence":"additional","affiliation":[{"name":"School of Architecture & Art Design, Hebei University of Technology, Tianjin 300131, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5087-7092","authenticated-orcid":false,"given":"Mengyang","family":"Ren","sequence":"additional","affiliation":[{"name":"Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhongxia","family":"Xiang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Tianjin University, Tianjin 300354, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1080\/10803548.2007.11076722","article-title":"Office Ergonomics: Deficiencies in Computer Workstation Design","volume":"13","author":"Shikdar","year":"2007","journal-title":"Int. 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