{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T16:57:08Z","timestamp":1793206628384,"version":"4.5.0"},"reference-count":29,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,4,15]],"date-time":"2025-04-15T00:00:00Z","timestamp":1744675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Consejo Superior de Deportes (Uni\u00f3n Europea-Next Generation EU)","award":["EXP 75053"],"award-info":[{"award-number":["EXP 75053"]}]},{"name":"Consejo Superior de Deportes (Uni\u00f3n Europea-Next Generation EU)","award":["PID2022-140556OB-I00"],"award-info":[{"award-number":["PID2022-140556OB-I00"]}]},{"name":"Consejo Superior de Deportes (Uni\u00f3n Europea-Next Generation EU)","award":["TED2021-130459BI00"],"award-info":[{"award-number":["TED2021-130459BI00"]}]},{"name":"Consejo Superior de Deportes (Uni\u00f3n Europea-Next Generation EU)","award":["T39_23R"],"award-info":[{"award-number":["T39_23R"]}]},{"name":"Agencia Estatal de Investigaci\u00f3n-Ministerio de Ciencia e Innovaci\u00f3n","award":["EXP 75053"],"award-info":[{"award-number":["EXP 75053"]}]},{"name":"Agencia Estatal de Investigaci\u00f3n-Ministerio de Ciencia e Innovaci\u00f3n","award":["PID2022-140556OB-I00"],"award-info":[{"award-number":["PID2022-140556OB-I00"]}]},{"name":"Agencia Estatal de Investigaci\u00f3n-Ministerio de Ciencia e Innovaci\u00f3n","award":["TED2021-130459BI00"],"award-info":[{"award-number":["TED2021-130459BI00"]}]},{"name":"Agencia Estatal de Investigaci\u00f3n-Ministerio de Ciencia e Innovaci\u00f3n","award":["T39_23R"],"award-info":[{"award-number":["T39_23R"]}]},{"name":"Gobierno de Arag\u00f3n","award":["EXP 75053"],"award-info":[{"award-number":["EXP 75053"]}]},{"name":"Gobierno de Arag\u00f3n","award":["PID2022-140556OB-I00"],"award-info":[{"award-number":["PID2022-140556OB-I00"]}]},{"name":"Gobierno de Arag\u00f3n","award":["TED2021-130459BI00"],"award-info":[{"award-number":["TED2021-130459BI00"]}]},{"name":"Gobierno de Arag\u00f3n","award":["T39_23R"],"award-info":[{"award-number":["T39_23R"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study aimed to evaluate the intra- and inter-instrument variability and reliability of the Axivity AX6 accelerometer under controlled technical conditions and human motion scenarios. In the first experiment, 12 accelerometers were affixed to a vibration platform and tested at four frequencies (2.2, 3.2, 6.5, and 9.4 Hz) along three axes to assess frequency- and axis-dependent variability. In the second experiment, four AX6 accelerometers were simultaneously placed on a subject\u2019s wrist and tested under four human motion conditions (walking at 4 km\u00b7h\u22121 and 6 km\u00b7h\u22121 and running at 8 km\u00b7h\u22121 and 10 km\u00b7h\u22121). Results demonstrated low intra- and inter-instrument variability (CVintra: 3.3\u20134.5%; CVinter: 6.3\u20137.7%) with high reliability (ICC = 0.98). Similar results were observed in human motion conditions (CVintra: 5.3\u20138.8%; CVinter: 7.1\u201310.4%), with ICC values of 0.98 for combined devices, and 0.99 for each device individually. Despite statistically significant differences (p &lt; 0.05) between devices in human motion all conditions, the variations remained below the minimal clinically significant difference threshold. These findings indicate that under technical conditions on a vibrating platform, and within the range of typical human accelerations, the Axivity AX6 is a reliable tool for measuring accelerations representative of physical activity. However, further research is necessary to validate its performance under free-living conditions.<\/jats:p>","DOI":"10.3390\/s25082480","type":"journal-article","created":{"date-parts":[[2025,4,15]],"date-time":"2025-04-15T03:59:06Z","timestamp":1744689546000},"page":"2480","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Variability and Reliability of the Axivity AX6 Accelerometer in Technical and Human Motion Conditions"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-9490-5163","authenticated-orcid":false,"given":"Marcos","family":"Echevarr\u00eda-Polo","sequence":"first","affiliation":[{"name":"EXER-GENUD \u201cGrowth, Exercise, NUtrition and Development\u201d Research Group, University of Zaragoza, 50009 Zaragoza, Spain"},{"name":"Faculty of Health and Sports Sciences, University of Zaragoza, 22001 Huesca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro J.","family":"Mar\u00edn","sequence":"additional","affiliation":[{"name":"CYMO Research Institute, 47140 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1960-407X","authenticated-orcid":false,"given":"Esther","family":"Pueyo","sequence":"additional","affiliation":[{"name":"BSICos Group, I3A, IIS Arag\u00f3n, University of Zaragoza, 50018 Zaragoza, Spain"},{"name":"Centro de Investigaci\u00f3n Biom\u00e9dica en Red de Bioingenier\u00eda, Biomateriales y Nanomedicina, 50018 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Javier","family":"Ramos Maqueda","sequence":"additional","affiliation":[{"name":"BSICos Group, I3A, IIS Arag\u00f3n, University of Zaragoza, 50018 Zaragoza, Spain"},{"name":"Arrhythmias Unit, Cardiology Department, Hospital Cl\u00ednico Universitario Lozano Blesa, 50009 Zaragoza, Spain"},{"name":"GIIS032 Research Group, Centro de Investigaci\u00f3n Biom\u00e9dica de Arag\u00f3n, 50009 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8374-9081","authenticated-orcid":false,"given":"Nuria","family":"Garatachea","sequence":"additional","affiliation":[{"name":"EXER-GENUD \u201cGrowth, Exercise, NUtrition and Development\u201d Research Group, University of Zaragoza, 50009 Zaragoza, Spain"},{"name":"Faculty of Health and Sports Sciences, University of Zaragoza, 22001 Huesca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1186\/s12966-015-0314-1","article-title":"Systematic review of the validity and reliability of consumer-wearable activity trackers","volume":"12","author":"Evenson","year":"2015","journal-title":"Int. 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