{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T19:50:05Z","timestamp":1780084205492,"version":"3.54.0"},"reference-count":30,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,3,5]],"date-time":"2024-03-05T00:00:00Z","timestamp":1709596800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000006","name":"Office of Naval Research","doi-asserted-by":"publisher","award":["N62909-21-1-2015"],"award-info":[{"award-number":["N62909-21-1-2015"]}],"id":[{"id":"10.13039\/100000006","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The ability to estimate lower-extremity mechanics in real-world scenarios may untether biomechanics research from a laboratory environment. This is particularly important for military populations where outdoor ruck marches over variable terrain and the addition of external load are cited as leading causes of musculoskeletal injury As such, this study aimed to examine (1) the validity of a minimal IMU sensor system for quantifying lower-extremity kinematics during treadmill walking and running compared with optical motion capture (OMC) and (2) the sensitivity of this IMU system to kinematic changes induced by load, grade, or a combination of the two. The IMU system was able to estimate hip and knee range of motion (ROM) with moderate accuracy during walking but not running. However, SPM analyses revealed IMU and OMC kinematic waveforms were significantly different at most gait phases. The IMU system was capable of detecting kinematic differences in knee kinematic waveforms that occur with added load but was not sensitive to changes in grade that influence lower-extremity kinematics when measured with OMC. While IMUs may be able to identify hip and knee ROM during gait, they are not suitable for replicating lab-level kinematic waveforms.<\/jats:p>","DOI":"10.3390\/s24051675","type":"journal-article","created":{"date-parts":[[2024,3,5]],"date-time":"2024-03-05T03:03:20Z","timestamp":1709607800000},"page":"1675","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["IMUs Can Estimate Hip and Knee Range of Motion during Walking Tasks but Are Not Sensitive to Changes in Load or Grade"],"prefix":"10.3390","volume":"24","author":[{"given":"AuraLea","family":"Fain","sequence":"first","affiliation":[{"name":"Biomechanics, Physical Performance and Exercise Research Group, Department of Health, Medicine and Human Sciences, Macquarie University\u2019s Biomechanics, Sydney, NSW 2113, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayden","family":"McCarthy","sequence":"additional","affiliation":[{"name":"Biomechanics, Physical Performance and Exercise Research Group, Department of Health, Medicine and Human Sciences, Macquarie University\u2019s Biomechanics, Sydney, NSW 2113, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bradley C.","family":"Nindl","sequence":"additional","affiliation":[{"name":"Neuromuscular Research Laboratory\/Warrior Performance Center, Department of Sports Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joel T.","family":"Fuller","sequence":"additional","affiliation":[{"name":"Biomechanics, Physical Performance and Exercise Research Group, Department of Health, Medicine and Human Sciences, Macquarie University\u2019s Biomechanics, Sydney, NSW 2113, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jodie A.","family":"Wills","sequence":"additional","affiliation":[{"name":"Biomechanics, Physical Performance and Exercise Research Group, Department of Health, Medicine and Human Sciences, Macquarie University\u2019s Biomechanics, Sydney, NSW 2113, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tim L. A.","family":"Doyle","sequence":"additional","affiliation":[{"name":"Biomechanics, Physical Performance and Exercise Research Group, Department of Health, Medicine and Human Sciences, Macquarie University\u2019s Biomechanics, Sydney, NSW 2113, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hindle, B.R., Keogh, J.W., and Lorimer, A.V. (2020). Validation of Spatiotemporal and Kinematic Measures in Functional Exercises Using a Minimal Modeling Inertial Sensor Methodology. Sensors, 20.","DOI":"10.3390\/s20164586"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Mavor, M.P., Ross, G.B., Clouthier, A.L., Karakolis, T., and Graham, R.B. (2020). Validation of an IMU Suit for Military-Based Tasks. 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