{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T10:25:05Z","timestamp":1771928705752,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T00:00:00Z","timestamp":1771027200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Prolonged tablet use for digital handwriting is increasingly common in educational settings, yet optimal ergonomic positioning remains unclear. This exploratory, cross-sectional study examined how tablet tilt angle affects hand and wrist muscle activation patterns during digital handwriting. Methods: This cross-sectional study recruited fifteen healthy university students (age 22.3 \u00b1 2.2 years) who completed standardized writing tasks at three tablet tilt angles (0\u00b0, 20\u00b0, 60\u00b0). Surface electromyography recorded activation from four muscles responsible for the dynamic tripod grip: abductor pollicis brevis (APB), flexor pollicis longus (FPL), flexor digitorum superficialis (FDS), and extensor carpi ulnaris (ECU). Results: Significant differences in muscle activation were observed across angles (p &lt; 0.05) for three muscles. APB activation was higher at 0\u00b0 (18.68 \u00b1 11.88% MVIC) and 20\u00b0 (18.72 \u00b1 12.13% MVIC) than at 60\u00b0 (14.67 \u00b1 10.38% MVIC), while FDS use decreased from 0\u00b0 (10.98 \u00b1 4.80% MVIC) to 60\u00b0 (6.43 \u00b1 3.14% MVIC). Conversely, ECU use increased from 0\u00b0 (11.76 \u00b1 6.96% MVIC) to 60\u00b0 (16.15 \u00b1 8.02% MVIC). FPL showed no significant differences. Conclusions: Tablet tilt angle substantially affects neuromuscular activation patterns during digital handwriting. In healthy young adults, these findings may help inform preventive ergonomic strategies for prolonged tablet handwriting; however, direct clinical extrapolation requires validation in clinical and more diverse populations.<\/jats:p>","DOI":"10.3390\/jcm15041514","type":"journal-article","created":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T08:38:39Z","timestamp":1771231119000},"page":"1514","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effects of Tablet Tilt Angle on Hand and Wrist Muscle Activation During Digital Handwriting: A Cross-Sectional Electromyographic Study in University Students"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5526-1147","authenticated-orcid":false,"given":"Shanyuan","family":"Meng","sequence":"first","affiliation":[{"name":"Department of Physical Therapy, College of Health Sciences, Dankook University, 119, Dandae-ro, Dongnam-gu, Cheonan-si 31116, Chungcheongnam-do, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong-Kyun","family":"Koo","sequence":"additional","affiliation":[{"name":"Regional Innovation System & Education Center, Industry-Academic Cooperation Foundation, Wonkwang Health Science University, 514, Iksan-daero, Iksan-si 54538, Jeonbuk-do, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jung-Won","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy, College of Health Sciences, Dankook University, 119, Dandae-ro, Dongnam-gu, Cheonan-si 31116, Chungcheongnam-do, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,14]]},"reference":[{"key":"ref_1","unstructured":"KISDI (2022). Key Results of the Korea Media Panel Survey, Korea Information Society Development Institute."},{"key":"ref_2","first-page":"1183","article-title":"Evaluating the impact of writing surface and configuration on muscle activation level during a handwriting task: An exploratory study","volume":"71","author":"Yerebakan","year":"2022","journal-title":"Work"},{"key":"ref_3","first-page":"301","article-title":"Effective adoption of tablets in post-secondary education: Recommendations based on a trial of iPads in university classes","volume":"11","author":"Mang","year":"2012","journal-title":"J. Inf. Technol. Educ. Innov. Pract."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1007\/s002210000495","article-title":"Interjoint coordination during handwriting-like movements","volume":"135","author":"Dounskaia","year":"2000","journal-title":"Exp. Brain Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"451","DOI":"10.1007\/BF00229422","article-title":"Development of human precision grip I: Basic coordination of force","volume":"85","author":"Forssberg","year":"1991","journal-title":"Exp. Brain Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1793","DOI":"10.1016\/S1388-2457(01)00623-X","article-title":"Precision grip deficits in cerebellar disorders in man","volume":"112","author":"Fellows","year":"2001","journal-title":"Clin. Neurophysiol."},{"key":"ref_7","first-page":"115","article-title":"A review of the handwriting assessment and characteristics of children with cerebral palsy","volume":"5","author":"Jeong","year":"2004","journal-title":"J. Spec. Educ. Theor. Pract."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1111\/j.1440-1630.2012.01014.x","article-title":"Effect of pencil grasp on the speed and legibility of handwriting after a 10-minute copy task in Grade 4 children","volume":"59","author":"Schwellnus","year":"2012","journal-title":"Aust. Occup. Ther. J."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"187.e1","DOI":"10.1016\/j.jhsa.2021.03.026","article-title":"Ulnar extension coupling in functional wrist kinematics during hand activities of daily living","volume":"47","author":"Nadeem","year":"2022","journal-title":"J. Hand Surg."},{"key":"ref_10","first-page":"161","article-title":"The Effects of Wrist Supporter and Kinesio Taping on Grip Strength","volume":"3","author":"Yeo","year":"2008","journal-title":"J. Korean Soc. Phys. Med."},{"key":"ref_11","first-page":"59","article-title":"Wrist and shoulder posture and muscle activity during touch-screen tablet use: Effects of usage configuration, tablet type, and interacting hand","volume":"45","author":"Young","year":"2013","journal-title":"Work"},{"key":"ref_12","first-page":"917","article-title":"Exploration of the associations of touch-screen tablet computer usage and musculoskeletal discomfort","volume":"53","author":"Chiang","year":"2016","journal-title":"Work"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"900","DOI":"10.1080\/00140139.2021.1873423","article-title":"Influence of neck flexion angle on gravitational moment and neck muscle activity when using a smartphone while standing","volume":"64","author":"Tapanya","year":"2021","journal-title":"Ergonomics"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"113","DOI":"10.13066\/kspm.2015.10.4.113","article-title":"Effect of shoulder external rotation on EMG activity of the scapular upward rotators during arm elevation","volume":"10","author":"Jung","year":"2015","journal-title":"J. Korean Soc. Phys. Med."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Rungkitlertsakul, S., Bhuanantanondh, P., and Buchholz, B. (2023). The effect of tablet tilt angles and time on posture, muscle activity, and discomfort at the neck and shoulder in healthy young adults. PLoS ONE, 18.","DOI":"10.1371\/journal.pone.0283521"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"e15654","DOI":"10.1016\/j.heliyon.2023.e15654","article-title":"Effect of tablet tilt positioning on ergonomic risks and respiratory function","volume":"9","author":"Vannajak","year":"2023","journal-title":"Heliyon"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1518\/001872099779591178","article-title":"The effects of complex wrist and forearm posture on wrist range of motion","volume":"41","author":"Marshall","year":"1999","journal-title":"Hum. Factors"},{"key":"ref_18","first-page":"207","article-title":"The effect of tablet tilt angle on users\u2019 preferences, postures, and performance","volume":"47","author":"Albin","year":"2014","journal-title":"Work"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Kim, S., Jung, J.-Y., Yang, C.-M., Lee, Y.-K., and Kim, J.-J. (2022). Development of an Ergonomic Writing Assistive Device for Finger Pain Reduction in the Elderly. Appl. Sci., 12.","DOI":"10.3390\/app12030993"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1111\/lit.12173","article-title":"Systematic review of young children\u2019s writing on screen: What do we know and what do we need to know","volume":"53","author":"Kucirkova","year":"2019","journal-title":"Literacy"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"719","DOI":"10.1016\/j.jelekin.2008.07.006","article-title":"Surface EMG: The issue of electrode location","volume":"19","author":"Mesin","year":"2009","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"97","DOI":"10.13066\/kspm.2016.11.3.97","article-title":"The effects of a bridging exercise applying changes in the base of support for the shoulders on trunk muscle activation","volume":"11","author":"Lee","year":"2016","journal-title":"J. Korean Soc. Phys. Med."},{"key":"ref_23","unstructured":"Neumann, D.A. (2002). Kinesiology of the Musculoskeletal System, Mosby."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1007\/s40846-017-0232-6","article-title":"Effects of carpal tunnel syndrome on force coordination and muscle coherence during precision pinch","volume":"37","author":"Lu","year":"2017","journal-title":"J. Med. Biol. Eng."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e367","DOI":"10.1016\/j.jhsa.2016.07.100","article-title":"The effect of wrist position on grip endurance and grip strength","volume":"41","author":"Lee","year":"2016","journal-title":"J. Hand Surg."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"440","DOI":"10.1016\/j.jelekin.2005.08.005","article-title":"Effects of wrist position and contraction on wrist flexors H-reflex, and its functional implications","volume":"16","author":"Chen","year":"2006","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"874","DOI":"10.1152\/jn.1994.71.3.874","article-title":"In vivo measurement of human wrist extensor muscle sarcomere length changes","volume":"71","author":"Lieber","year":"1994","journal-title":"J. Neurophysiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"816","DOI":"10.1093\/ptj\/83.9.816","article-title":"Effect of computer keyboard slope on wrist position and forearm electromyography of typists without musculoskeletal disorders","volume":"83","author":"Simoneau","year":"2003","journal-title":"Phys. Ther."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/4\/1514\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T09:39:14Z","timestamp":1771925954000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/4\/1514"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,14]]},"references-count":28,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["jcm15041514"],"URL":"https:\/\/doi.org\/10.3390\/jcm15041514","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,14]]}}}