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FleXo, a lightweight (1.35 kg), flexible, ergonomic, and passive back-support exoskeleton is intended to reduce lower back strain during lifting tasks while allowing full freedom of movement for activities like walking, sitting, or side bending. FleXo\u2019s design results from an advanced multi-objective design optimization approach that balances functionality and user comfort. In this work, validated through user feedback in a series of relevant repetitive tasks, it is demonstrated that FleXo can reduce the perceived physical effort during lifting tasks, enhance user satisfaction, improve employee wellbeing, promote workplace safety, decrease injuries, and lower the costs (both to society and companies) associated with lower back pain and injury.<\/jats:p>","DOI":"10.3389\/frobt.2025.1687825","type":"journal-article","created":{"date-parts":[[2025,10,23]],"date-time":"2025-10-23T04:12:58Z","timestamp":1761192778000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["FleXo: a flexible passive exoskeleton optimized for reducing lower back strain in manual handling tasks"],"prefix":"10.3389","volume":"12","author":[{"given":"Federico","family":"Allione","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Lazzaroni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonios E.","family":"Gkikakis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Di Natali","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luigi","family":"Monica","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Darwin G.","family":"Caldwell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jes\u00fas","family":"Ortiz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,10,23]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"456","DOI":"10.1016\/j.clinbiomech.2005.12.021","article-title":"An on-body personal lift augmentation device (PLAD) reduces EMG amplitude of erector spinae during lifting tasks","volume":"21","author":"Abdoli-E","year":"2006","journal-title":"Clin. 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