{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T20:59:18Z","timestamp":1765486758268,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,4,8]],"date-time":"2022-04-08T00:00:00Z","timestamp":1649376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Concussion is the most common injury in professional Rugby Union (RU) players, with increasing incidence and severity each year. Strengthening the neck is an intervention used to decrease concussion incidence and severity, which can only be proven effective if strength neck measures are reliable. We conducted a repeated-measures reliability study with 23 male RU players. Neck strength was assessed seated in a \u2018make\u2019 test fashion in flexion, extension, and bilateral-side flexion. Flexion-to-extension and left-to-right side ratios were also computed. Three testing sessions were undertaken over three consecutive weeks. Intrasession and intersession reliabilities were assessed using typical errors, coefficient of variations (CV), and intraclass correlation coefficients (ICC). Intrasession reliability demonstrated good-to-excellent relative (ICC &gt; 0.75) and good absolute (CV \u2264 20%) reliability in all directions (ICC = 0.86\u20130.95, CV = 6.4\u20138.8%), whereas intersession reliability showed fair relative (ICC: 0.40 to 0.75) and acceptable absolute (CV \u2264 20%) reliability for mean and maximal values (ICC = 0.51\u20130.69, CV = 14.5\u201319.8%). Intrasession reliability for flexion-to-extension ratio was good (relative, ICC = 0.86) and acceptable (absolute, CV = 11.5%) and was fair (relative, ICC = 0.75) and acceptable (absolute, CV = 11.5%) for left-to-right ratio. Intersession ratios from mean and maximal values were fair (relative, ICC = 0.52\u20130.55) but not always acceptable (absolute, CV = 16.8\u201324%). Assessing isometric neck strength with a head harness and a cable with a load cell device seated in semi-professional RU players is feasible and demonstrates good-to-excellent intrasession and fair intersession reliability. We provide data from RU players to inform practice and assist standardisation of testing methods.<\/jats:p>","DOI":"10.3390\/s22082872","type":"journal-article","created":{"date-parts":[[2022,4,9]],"date-time":"2022-04-09T05:13:08Z","timestamp":1649481188000},"page":"2872","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Reliability of Repeated Isometric Neck Strength in Rugby Union Players Using a Load Cell Device"],"prefix":"10.3390","volume":"22","author":[{"given":"Christian","family":"Chavarro-Nieto","sequence":"first","affiliation":[{"name":"Division of Health, Engineering, Computing and Science, Te Huataki Waiora School of Health, University of Waikato, Adams Centre for High Performance, Tauranga 3116, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2900-7460","authenticated-orcid":false,"given":"Martyn","family":"Beaven","sequence":"additional","affiliation":[{"name":"Division of Health, Engineering, Computing and Science, Te Huataki Waiora School of Health, University of Waikato, Adams Centre for High Performance, Tauranga 3116, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicholas","family":"Gill","sequence":"additional","affiliation":[{"name":"Division of Health, Engineering, Computing and Science, Te Huataki Waiora School of Health, University of Waikato, Adams Centre for High Performance, Tauranga 3116, New Zealand"},{"name":"New Zealand Rugby, Wellington 6011, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1087-4986","authenticated-orcid":false,"given":"Kim","family":"H\u00e9bert-Losier","sequence":"additional","affiliation":[{"name":"Division of Health, Engineering, Computing and Science, Te Huataki Waiora School of Health, University of Waikato, Adams Centre for High Performance, Tauranga 3116, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"676","DOI":"10.1136\/bjsports-2020-102529","article-title":"Trends in match injury risk in professional male rugby union: A 16-season review of 10 851 match injuries in the English Premiership (2002\u20132019): The Professional Rugby Injury Surveillance Project","volume":"55","author":"West","year":"2020","journal-title":"Br. 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