{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T15:35:37Z","timestamp":1772897737313,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,7]],"date-time":"2025-04-07T00:00:00Z","timestamp":1743984000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["BDCC"],"abstract":"<jats:p>Walking is a fundamental human activity, and analyzing its complexities is essential for understanding gait abnormalities and musculoskeletal disorders. This article delves into the classification of gait phases using advanced machine learning techniques, specifically focusing on dividing these phases into five distinct subphases. The study utilizes data from 100 individuals obtained from an open-access platform and employs two distinct training methodologies. The first approach adopts stratified random sampling, where 80% of the data from each subphase are allocated for training and 20% for testing. The second approach involves participant-based splitting, training on data from 80% of the individuals and testing on the remaining 20%. Preprocessing methods such as Min\u2013Max Scaling (MMS), Standard Scaling (SS), and Principal Component Analysis (PCA) were applied to the dataset to ensure optimal performance of the machine learning models. Several algorithms were implemented, including k-Nearest Neighbors (k-NNs), Logistic Regression (LR), Decision Tree (DT), Random Forest (RF), Support Vector Machine (SVM), Naive Bayes (Gaussian, Bernoulli, and Multinomial) (NB), Linear Discriminant Analysis (LDA), and Quadratic Discriminant Analysis (QDA). The models were rigorously evaluated using performance metrics like cross-validation score, Mean Squared Error (MSE), Root Mean Squared Error (RMSE), accuracy, and R2 score, offering a comprehensive assessment of their effectiveness in classifying gait phases. In the five subphases analysis, RF again performed strongly with a 94.95% accuracy, an RMSE of 0.4461, and an R2 score of 90.09%, demonstrating robust performance across all scaling methods.<\/jats:p>","DOI":"10.3390\/bdcc9040089","type":"journal-article","created":{"date-parts":[[2025,4,10]],"date-time":"2025-04-10T11:26:41Z","timestamp":1744284401000},"page":"89","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Quinary Classification of Human Gait Phases Using Machine Learning: Investigating the Potential of Different Training Methods and Scaling Techniques"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-4047-7202","authenticated-orcid":false,"given":"Amal","family":"Mekni","sequence":"first","affiliation":[{"name":"Laboratory of Robotics Informatics and Complex Systems (RISC Lab, LR16ES07), National Engineering School of Tunis, University of Tunis El Manar, B.P. 37, Le Belv\u00e9d\u00e8re, Tunis 1002, Tunisia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2499-6039","authenticated-orcid":false,"given":"Jyotindra","family":"Narayan","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Indian Institute of Technology Patna, Patna 801106, India"},{"name":"Department of Computing, Imperial College London, London SWS 2AZ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5643-134X","authenticated-orcid":false,"given":"Hass\u00e8ne","family":"Gritli","sequence":"additional","affiliation":[{"name":"Laboratory of Robotics Informatics and Complex Systems (RISC Lab, LR16ES07), National Engineering School of Tunis, University of Tunis El Manar, B.P. 37, Le Belv\u00e9d\u00e8re, Tunis 1002, Tunisia"},{"name":"Higher Institute of Information and Communication Technologies, University of Carthage, Technopole of Borj C\u00e9dria, Route de Soliman, B.P. 123, Hammam Chatt, Ben Arous 1164, Tunisia"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"775","DOI":"10.1007\/s12369-020-00662-9","article-title":"Development of active lower limb robotic-based orthosis and exoskeleton devices: A systematic review","volume":"13","author":"Kalita","year":"2021","journal-title":"Int. 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