{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T06:07:09Z","timestamp":1784009229835,"version":"3.55.0"},"reference-count":49,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2019,8,25]],"date-time":"2019-08-25T00:00:00Z","timestamp":1566691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006360","name":"Bundesministerium f\u00fcr Wirtschaft und Energie","doi-asserted-by":"publisher","award":["4136601TS5"],"award-info":[{"award-number":["4136601TS5"]}],"id":[{"id":"10.13039\/501100006360","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Knee joint forces (KJF) are biomechanical measures used to infer the load on knee joint structures. The purpose of this study is to develop an artificial neural network (ANN) that estimates KJF during sport movements, based on data obtained by wearable sensors. Thirteen participants were equipped with two inertial measurement units (IMUs) located on the right leg. Participants performed a variety of movements, including linear motions, changes of direction, and jumps. Biomechanical modelling was carried out to determine KJF. An ANN was trained to model the association between the IMU signals and the KJF time series. The ANN-predicted KJF yielded correlation coefficients that ranged from 0.60 to 0.94 (vertical KJF), 0.64 to 0.90 (anterior\u2013posterior KJF) and 0.25 to 0.60 (medial\u2013lateral KJF). The vertical KJF for moderate running showed the highest correlation (0.94 \u00b1 0.33). The summed vertical KJF and peak vertical KJF differed between calculated and predicted KJF across all movements by an average of 5.7% \u00b1 5.9% and 17.0% \u00b1 13.6%, respectively. The vertical and anterior\u2013posterior KJF values showed good agreement between ANN-predicted outcomes and reference KJF across most movements. This study supports the use of wearable sensors in combination with ANN for estimating joint reactions in sports applications.<\/jats:p>","DOI":"10.3390\/s19173690","type":"journal-article","created":{"date-parts":[[2019,8,26]],"date-time":"2019-08-26T04:38:23Z","timestamp":1566794303000},"page":"3690","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":126,"title":["Estimation of Knee Joint Forces in Sport Movements Using Wearable Sensors and Machine Learning"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5291-4299","authenticated-orcid":false,"given":"Bernd J.","family":"Stetter","sequence":"first","affiliation":[{"name":"Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steffen","family":"Ringhof","sequence":"additional","affiliation":[{"name":"Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany"},{"name":"Department of Sport and Sport Science, University of Freiburg, 79117 Freiburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frieder C.","family":"Krafft","sequence":"additional","affiliation":[{"name":"Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Sell","sequence":"additional","affiliation":[{"name":"Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany"},{"name":"Joint Center Black Forest, Hospital Neuenbuerg, 75305 Neuenbuerg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thorsten","family":"Stein","sequence":"additional","affiliation":[{"name":"Institute of Sports and Sports Science, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1034\/j.1600-0838.2000.010002090.x","article-title":"A 7-year study on risks and costs of knee injuries in male and female youth participants in 12 sports","volume":"10","author":"Loes","year":"2000","journal-title":"Scand. 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