{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T16:56:18Z","timestamp":1772211378450,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T00:00:00Z","timestamp":1772150400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008723","name":"University of C\u00e1diz","doi-asserted-by":"publisher","award":["AT2016-38"],"award-info":[{"award-number":["AT2016-38"]}],"id":[{"id":"10.13039\/501100008723","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Biomedical Research Networking Center on Frailty and Healthy Aging","award":["CB16\/10\/00477"],"award-info":[{"award-number":["CB16\/10\/00477"]}]},{"name":"EXERNET Research Network on Exercise and Health in Special Populations","award":["DEP2005-00046\/ACTI"],"award-info":[{"award-number":["DEP2005-00046\/ACTI"]}]},{"DOI":"10.13039\/501100011011","name":"Andalusian Government, Andalusian Health Service","doi-asserted-by":"publisher","award":["PI0068-2018"],"award-info":[{"award-number":["PI0068-2018"]}],"id":[{"id":"10.13039\/501100011011","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Muscular fitness is a key component of health and athletic performance, and isometric strength is a widely used indicator. This study reports an agreement-based validation of the Isometric Strength Measurement Device (ISOMETRO) for upper-limb isometric tension measurements under controlled laboratory conditions. Twenty-one healthy young amateur rock climbers (11 men and 10 women) performed four upper-limb tensile tests (shoulder adduction at 90\u00b0, shoulder adduction at 60\u00b0, shoulder extension at 90\u00b0, and elbow extension at 90\u00b0). Agreement with an independent criterion device was evaluated using a force plate, while a series-connected load cell was used as an internal consistency check of the measurement chain. Linear mixed-effects models showed that ISOMETRO strongly predicted force plate values (\u03b2 = 0.999, SE = 0.002, p &lt; 0.001), with a marginal R2 &gt; 0.99. Bland\u2013Altman analysis indicated negligible bias (\u22120.08 N) and narrow limits of agreement (\u22124.97 to 4.81 N), and concordance was excellent (CCC \u2265 0.996). The series-connected load cell comparison also showed near-unity agreement (\u03b2 = 0.998, SE = 0.003, p &lt; 0.001), supporting internal measurement chain integrity. These findings support excellent agreement between ISOMETRO and force plate measurements for upper-limb tensile isometric testing along the vertical axis in young amateur rock climbers under controlled laboratory conditions. However, given the specific sample characteristics and the strictly vertical laboratory configuration, these results should not be generalized to other populations, joint angles, force directions, or non-laboratory environments without further validation. Further studies are needed to confirm performance in more diverse contexts and to establish reliability for repeated-measurement applications.<\/jats:p>","DOI":"10.3390\/s26051504","type":"journal-article","created":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T15:52:38Z","timestamp":1772207558000},"page":"1504","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Agreement-Based Validation of ISOMETRO for Upper-Limb Isometric Tension Measurements"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6867-7718","authenticated-orcid":false,"given":"Jos\u00e9 Luis","family":"Gonz\u00e1lez-Montesinos","sequence":"first","affiliation":[{"name":"Department of Physical Education, Faculty of Education Sciences, University of C\u00e1diz, 11519 C\u00e1diz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5047-2976","authenticated-orcid":false,"given":"Jorge del Rosario","family":"Fern\u00e1ndez-Santos","sequence":"additional","affiliation":[{"name":"Biomedical Research and Innovation Institute of C\u00e1diz (INiBICA) Research Unit, 11009 C\u00e1diz, Spain"},{"name":"GALENO Research Group and Department of Physical Education, Faculty of Education Sciences, University of C\u00e1diz, 11519 C\u00e1diz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8977-4744","authenticated-orcid":false,"given":"David","family":"Jim\u00e9nez-Pav\u00f3n","sequence":"additional","affiliation":[{"name":"Biomedical Research and Innovation Institute of C\u00e1diz (INiBICA) Research Unit, 11009 C\u00e1diz, Spain"},{"name":"MOVE-IT Research Group and Department of Physical Education, Faculty of Education Sciences, University of C\u00e1diz, 11519 C\u00e1diz, Spain"},{"name":"CIBER of Frailty and Healthy Aging (CIBERFES), 28029 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1826-1463","authenticated-orcid":false,"given":"Alejandro","family":"S\u00e1nchez-Delgado","sequence":"additional","affiliation":[{"name":"Computational Social Science DataLab (CS2 DataLab), University Research Institute for Sustainable Social Development (INDESS), University of C\u00e1diz, 11405 Jerez de la Frontera, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1956-3087","authenticated-orcid":false,"given":"Rub\u00e9n","family":"Arag\u00f3n-Mart\u00edn","sequence":"additional","affiliation":[{"name":"Biomedical Research and Innovation Institute of C\u00e1diz (INiBICA) Research Unit, 11009 C\u00e1diz, Spain"},{"name":"MOVE-IT Research Group and Department of Physical Education, Faculty of Education Sciences, University of C\u00e1diz, 11519 C\u00e1diz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juan Manuel","family":"Escudier-V\u00e1zquez","sequence":"additional","affiliation":[{"name":"Biomedical Research and Innovation Institute of C\u00e1diz (INiBICA) Research Unit, 11009 C\u00e1diz, Spain"},{"name":"MOVE-IT Research Group and Department of Physical Education, Faculty of Education Sciences, University of C\u00e1diz, 11519 C\u00e1diz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7984-1077","authenticated-orcid":false,"given":"Vanesa","family":"Espa\u00f1a-Romero","sequence":"additional","affiliation":[{"name":"Biomedical Research and Innovation Institute of C\u00e1diz (INiBICA) Research Unit, 11009 C\u00e1diz, Spain"},{"name":"MOVE-IT Research Group and Department of Physical Education, Faculty of Education Sciences, University of C\u00e1diz, 11519 C\u00e1diz, Spain"},{"name":"C-HIPPER Climbing Research Association, 11100 C\u00e1diz, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1177\/1359786810382057","article-title":"Review: Mortality trends in the general population: The importance of cardiorespiratory fitness","volume":"24","author":"Lee","year":"2010","journal-title":"J. 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