{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T00:52:09Z","timestamp":1777423929355,"version":"3.51.4"},"reference-count":54,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,5]],"date-time":"2021-06-05T00:00:00Z","timestamp":1622851200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Society for the Promotion of Science","award":["JP17K12995"],"award-info":[{"award-number":["JP17K12995"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Background: Loss of balance is a considerable risk factor for workers while using ladders, because they are required to maintain static postural balance on platforms of a restricted size. This study observed center of mass (CoM) and center of pressure (CoP) behaviors and evaluated the effects of the platform depth (anterior\u2013posterior length) and working postures. Methods: Eleven male participants stood on four platforms with depths ranging from 6 to 15 cm and maintained their positions for 60 s while performing or not performing other tasks (object holding, upward viewing, or both simultaneously). The kinematics were analyzed on the sagittal plane based on the inverse pendulum model. Results: The absolute moving range for the CoP\u2013CoM linearly increased with the decreasing platform depth, and the working postures affected the slopes of the linear fits. The relative range of CoP\u2013CoM displacement on narrow platforms was highly correlated with the subjective sense of instability. Conclusions: Monitoring the CoP is effective for a better understanding and evaluation of static postural balance. This study\u2019s findings contribute to improving the design of work equipment through the use of wider platforms that are robust against the effects of working postures.<\/jats:p>","DOI":"10.3390\/s21113909","type":"journal-article","created":{"date-parts":[[2021,6,7]],"date-time":"2021-06-07T01:56:40Z","timestamp":1623031000000},"page":"3909","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Analysis of Postural Instability in the Upright Position on Narrow Platforms and the Interactions with Postural Constraints"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4755-0566","authenticated-orcid":false,"given":"Atsushi","family":"Sugama","sequence":"first","affiliation":[{"name":"Risk Management Research Group, National Institute of Occupational Safety and Health, Tokyo 204-0024, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akihiko","family":"Seo","sequence":"additional","affiliation":[{"name":"Faculty of Systems Design, Tokyo Metropolitan University, Tokyo 191-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,5]]},"reference":[{"key":"ref_1","first-page":"17","article-title":"A scientometric analysis and review of fall from height research in construction","volume":"20","author":"Vigneshkumar","year":"2020","journal-title":"Constr. 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