{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T10:40:25Z","timestamp":1780396825373,"version":"3.54.1"},"reference-count":27,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2023,7,17]],"date-time":"2023-07-17T00:00:00Z","timestamp":1689552000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Singapore Armed Forces","award":["MINDEF 7\/21 KPW"],"award-info":[{"award-number":["MINDEF 7\/21 KPW"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The loadsol\u00ae wireless in-shoe force sensors can be useful for in-field measurements. However, its accuracy is unknown in the military context, whereby soldiers have to carry heavy loads and walk in military boots. The purpose of this study was to establish the validity of the loadsol\u00ae sensors in military personnel during loaded walking on flat, inclined and declined surfaces. Full-time Singapore Armed Forces (SAF) personnel (n = 8) walked on an instrumented treadmill on flat, 10\u00b0 inclined, and 10\u00b0 declined gradients while carrying heavy loads (25 kg and 35 kg). Normal ground reaction forces (GRF), perpendicular to the contact surface, were simultaneously measured using both the loadsol\u00ae sensors inserted in the military boots and the Bertec instrumented treadmill as the gold standard. A total of eight variables of interest were compared between loadsol\u00ae and treadmill, including four kinetic (impact peak force, active peak force, impulse, loading rate) and four spatiotemporal (stance time, stride time, cadence, step length) variables. Validity was assessed using Bland\u2013Altman plots and 95% Limits of Agreement (LoA). Bias was calculated as the mean difference between the values obtained from loadsol\u00ae and the instrumented treadmill. Results showed similar force-time profiles between loadsol\u00ae sensors and the instrumented treadmill. The bias of most variables was generally low, with a narrow range of LoA. The high accuracy and good agreement with standard laboratory equipment suggest that the loadsol\u00ae system is a valid tool for measuring normal GRF during walking in military boots under heavy load carriage.<\/jats:p>","DOI":"10.3390\/s23146465","type":"journal-article","created":{"date-parts":[[2023,7,18]],"date-time":"2023-07-18T01:46:02Z","timestamp":1689644762000},"page":"6465","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Validation of In-Shoe Force Sensors during Loaded Walking in Military Personnel"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9531-9214","authenticated-orcid":false,"given":"Pui Wah","family":"Kong","sequence":"first","affiliation":[{"name":"Physical Education and Sports Science Academic Group, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8037-2458","authenticated-orcid":false,"given":"Muhammad Nur Shahril","family":"Iskandar","sequence":"additional","affiliation":[{"name":"Physical Education and Sports Science Academic Group, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ang Hong","family":"Koh","sequence":"additional","affiliation":[{"name":"Physical Education and Sports Science Academic Group, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mei Yee Mavis","family":"Ho","sequence":"additional","affiliation":[{"name":"Physical Education and Sports Science Academic Group, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheryl Xue Er","family":"Lim","sequence":"additional","affiliation":[{"name":"Centre of Excellence for Soldier Performance, Singapore Armed Forces, Singapore 637901, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.gaitpost.2015.10.010","article-title":"Using Gait Parameters to Detect Fatigue and Responses to Ice Slurry during Prolonged Load Carriage","volume":"43","author":"Tay","year":"2016","journal-title":"Gait Posture"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1016\/S0749-3797(00)00114-8","article-title":"Military Training-Related Injuries Surveillance, Research, and Prevention","volume":"18","author":"Kaufman","year":"2000","journal-title":"Am. 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