{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T18:05:42Z","timestamp":1784657142459,"version":"3.55.0"},"reference-count":31,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T00:00:00Z","timestamp":1784592000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>This study investigated the immediate effects of three sitting positions, including chair sitting with and without a backrest and cross-legged sitting on the floor, on cervical and trunk postures, musculoskeletal discomfort, and ergonomic risk during smartphone gaming among young adults.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A randomized within-subject study was conducted in 41 healthy participants (mean age 20.4\u2009\u00b1\u20091.1 years). Each participant played Realm of Valor (ROV) on their personal smartphone for 20 minutes in three randomly assigned sitting positions. Cervical and trunk angles were measured using two-dimensional photogrammetry at baseline and at 5, 10, 15, and 20 minutes. Ergonomic risk was assessed using the Rapid Upper Limb Assessment (RULA), with the maximum score used for analysis. After each session, participants reported perceived musculoskeletal discomfort using a visual analog scale.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A significant interaction between time and sitting position was found for both neck flexion (F(3.87, 232.27) = 5.31, p\u2009&lt;\u20090.001, partial \u03b7\u00b2\u2009=\u20090.081) and trunk angles (F(8,480) = 2.73, p\u2009=\u20090.006, partial \u03b7\u00b2\u2009=\u20090.044). Perceived neck discomfort was the most common symptom, with the cross-legged position showing the highest prevalence (51.2%, Cochran\u2019s Q\u2009=\u20098.67, p\u2009=\u20090.013, Kendall\u2019s W\u2009=\u20090.106). However, symptom intensity did not differ significantly among positions. RULA scores also differed across sitting positions (\u03c7\u00b2(2) = 27.0, p\u2009&lt;\u20090.001, Kendall\u2019s W\u2009=\u20090.329), with the cross-legged position showing the highest score.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Sitting posture significantly affected cervical and trunk alignment, perceived discomfort, and ergonomic risk during smartphone gaming. Cross-legged sitting induced the greatest neck and trunk flexion, which may contribute to increased musculoskeletal strain over time. These findings emphasize the importance of promoting ergonomic awareness and healthy digital habits to maintain spinal alignment and reduce posture-related musculoskeletal strain; however, longitudinal studies are needed to confirm long-term effects.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0354360","type":"journal-article","created":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T17:28:18Z","timestamp":1784654898000},"page":"e0354360","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Immediate effects of sitting position on cervical and trunk posture, perceived discomfort, and RULA-based ergonomic risk during smartphone gaming: A randomized within-subject study"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8723-9350","authenticated-orcid":true,"given":"Patcharin","family":"Nilmart","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3568-4601","authenticated-orcid":true,"given":"Wantanee","family":"Yodchaisarn","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natdanai","family":"Vajidee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nounchanok","family":"Tansakul","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wirada","family":"Sramongkhol","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sasisom","family":"Leangsakul","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,7,21]]},"reference":[{"issue":"6","key":"pone.0354360.ref001","doi-asserted-by":"crossref","first-page":"2512","DOI":"10.18203\/2394-6040.ijcmph20182187","article-title":"Correlation of smartphone use addiction with text neck syndrome and SMS thumb in physiotherapy students","volume":"5","author":"PP Shah","year":"2018","journal-title":"Int J Commun Med Public Health"},{"key":"pone.0354360.ref002","doi-asserted-by":"crossref","DOI":"10.7717\/peerj.14443","article-title":"Prevalence of text neck posture, smartphone addiction, and its association with neck disorders among university students in the Kingdom of Saudi Arabia during the COVID-19 pandemic","volume":"10","author":"MS Sirajudeen","year":"2022","journal-title":"PeerJ"},{"issue":"4","key":"pone.0354360.ref003","doi-asserted-by":"crossref","first-page":"1565","DOI":"10.3390\/ijerph18041565","article-title":"Text Neck Syndrome in Children and Adolescents","volume":"18","author":"D David","year":"2021","journal-title":"Int J Environ Res Public Health"},{"issue":"2","key":"pone.0354360.ref004","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1080\/00140139.2014.967311","article-title":"Head flexion angle while using a smartphone","volume":"58","author":"S Lee","year":"2015","journal-title":"Ergonomics"},{"issue":"8","key":"pone.0354360.ref005","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1080\/09593985.2017.1328716","article-title":"The effects of smart phone gaming duration on muscle activation and spinal posture: Pilot study","volume":"33","author":"Ms Park J-H","year":"2017","journal-title":"Physiother Theory Pract"},{"issue":"1","key":"pone.0354360.ref006","doi-asserted-by":"crossref","DOI":"10.1080\/23311916.2021.1890368","article-title":"Effect of prolonged continuous smartphone gaming on upper body postures and fatigue of the neck muscles in school students aged between 10-18 years","volume":"8","author":"P Hanphitakphong","year":"2021","journal-title":"Cogent Eng"},{"issue":"6","key":"pone.0354360.ref007","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0285451","article-title":"Neck pain associated with smartphone usage among university students","volume":"18","author":"MF Maayah","year":"2023","journal-title":"PLoS One"},{"issue":"12","key":"pone.0354360.ref008","doi-asserted-by":"crossref","first-page":"1524","DOI":"10.1080\/00140139.2019.1661525","article-title":"Effect of neck flexion angles on neck muscle activity among smartphone users with and without neck pain","volume":"62","author":"S Namwongsa","year":"2019","journal-title":"Ergonomics"},{"key":"pone.0354360.ref009","doi-asserted-by":"crossref","first-page":"101952","DOI":"10.1016\/j.inat.2023.101952","article-title":"The impact of excessive use of smart portable devices on neck pain and associated musculoskeletal symptoms. 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