{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T07:55:19Z","timestamp":1770278119951,"version":"3.49.0"},"reference-count":56,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,25]],"date-time":"2020-11-25T00:00:00Z","timestamp":1606262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bundesministers f\u00fcrWissenschaft, Forschung und Wirtschaft","award":["COMET: Digital Motion in Sports, Fitness, & Well-being (872574)"],"award-info":[{"award-number":["COMET: Digital Motion in Sports, Fitness, & Well-being (872574)"]}]},{"DOI":"10.13039\/501100012416","name":"Bundesministerium f\u00fcr Digitalisierung und Wirtschaftsstandort","doi-asserted-by":"publisher","award":["COMET: Digital Motion in Sports, Fitness, & Well-being (872574)"],"award-info":[{"award-number":["COMET: Digital Motion in Sports, Fitness, & Well-being (872574)"]}],"id":[{"id":"10.13039\/501100012416","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The foot strike pattern performed during running is an important variable for runners, performance practitioners, and industry specialists. Versatile, wearable sensors may provide foot strike information while encouraging the collection of diverse information during ecological running. The purpose of the current study was to predict foot strike angle and classify foot strike pattern from LoadsolTM wearable pressure insoles using three machine learning techniques (multiple linear regression\u2015MR, conditional inference tree\u2015TREE, and random forest\u2015FRST). Model performance was assessed using three-dimensional kinematics as a ground-truth measure. The prediction-model accuracy was similar for the regression, inference tree, and random forest models (RMSE: MR = 5.16\u00b0, TREE = 4.85\u00b0, FRST = 3.65\u00b0; MAPE: MR = 0.32\u00b0, TREE = 0.45\u00b0, FRST = 0.33\u00b0), though the regression and random forest models boasted lower maximum precision (13.75\u00b0 and 14.3\u00b0, respectively) than the inference tree (19.02\u00b0). The classification performance was above 90% for all models (MR = 90.4%, TREE = 93.9%, and FRST = 94.1%). There was an increased tendency to misclassify mid foot strike patterns in all models, which may be improved with the inclusion of more mid foot steps during model training. Ultimately, wearable pressure insoles in combination with simple machine learning techniques can be used to predict and classify a runner\u2019s foot strike with sufficient accuracy.<\/jats:p>","DOI":"10.3390\/s20236737","type":"journal-article","created":{"date-parts":[[2020,11,25]],"date-time":"2020-11-25T08:59:15Z","timestamp":1606294755000},"page":"6737","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Foot Strike Angle Prediction and Pattern Classification Using LoadsolTM Wearable Sensors: A Comparison of Machine Learning Techniques"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4596-9304","authenticated-orcid":false,"given":"Stephanie R.","family":"Moore","sequence":"first","affiliation":[{"name":"Department of Sport and Exercise Science, University of Salzburg, Schlossallee 49, 5400 Hallein\/Rif, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2773-5034","authenticated-orcid":false,"given":"Christina","family":"Kranzinger","sequence":"additional","affiliation":[{"name":"Salzburg Research Forschungsgesellschaft m.b.H., Jakob-Haringer-Stra\u00dfe 5, 5020 Salzburg, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8773-4303","authenticated-orcid":false,"given":"Julian","family":"Fritz","sequence":"additional","affiliation":[{"name":"Adidas AG, Adi-Dassler-Strasse 1, 91074 Herzogenaurach, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6685-1540","authenticated-orcid":false,"given":"Thomas","family":"St\u04e7ggl","sequence":"additional","affiliation":[{"name":"Department of Sport and Exercise Science, University of Salzburg, Schlossallee 49, 5400 Hallein\/Rif, Austria"},{"name":"Athlete Performance Center, Red Bull Sports, Brunnbachweg 71, 5303 Thalgau, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Josef","family":"Kr\u04e7ll","sequence":"additional","affiliation":[{"name":"Department of Sport and Exercise Science, University of Salzburg, Schlossallee 49, 5400 Hallein\/Rif, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0380-8801","authenticated-orcid":false,"given":"Hermann","family":"Schwameder","sequence":"additional","affiliation":[{"name":"Department of Sport and Exercise Science, University of Salzburg, Schlossallee 49, 5400 Hallein\/Rif, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"793","DOI":"10.1007\/s40279-016-0474-4","article-title":"Is There an Economical Running Technique? 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