{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T14:38:44Z","timestamp":1775227124436,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2012,9,25]],"date-time":"2012-09-25T00:00:00Z","timestamp":1348531200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Monitoring the performance is a crucial task for elite sports during both training and competition. Velocity is the key parameter of performance in swimming, but swimming performance evaluation remains immature due to the complexities of measurements in water. The purpose of this study is to use a single inertial measurement unit (IMU) to estimate front crawl velocity. Thirty swimmers, equipped with an IMU on the sacrum, each performed four different velocity trials of 25 m in ascending order. A tethered speedometer was used as the velocity measurement reference. Deployment of biomechanical constraints of front crawl locomotion and change detection framework on acceleration signal paved the way for a drift-free integration of forward acceleration using IMU to estimate the swimmers velocity. A difference of 0.6 \u00b1 5.4 cm\u00b7s\u22121 on mean cycle velocity and an RMS difference of 11.3 cm\u00b7s\u22121 in instantaneous velocity estimation were observed between IMU and the reference. The most important contribution of the study is a new practical tool for objective evaluation of swimming performance. A single body-worn IMU provides timely feedback for coaches and sport scientists without any complicated setup or restraining the swimmer\u2019s natural technique.<\/jats:p>","DOI":"10.3390\/s121012927","type":"journal-article","created":{"date-parts":[[2012,9,25]],"date-time":"2012-09-25T20:54:33Z","timestamp":1348606473000},"page":"12927-12939","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":77,"title":["Front-Crawl Instantaneous Velocity Estimation Using a Wearable Inertial Measurement Unit"],"prefix":"10.3390","volume":"12","author":[{"given":"Farzin","family":"Dadashi","sequence":"first","affiliation":[{"name":"Laboratory of Movement Analysis and Measurement, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne (EPFL), 1015 Lausanne, Switzerland"}]},{"given":"Florent","family":"Crettenand","sequence":"additional","affiliation":[{"name":"Institute of Sport Sciences, University of Lausanne, 1015 Lausanne, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8081-4423","authenticated-orcid":false,"given":"Gr\u00e9goire P.","family":"Millet","sequence":"additional","affiliation":[{"name":"Institute of Sport Sciences, University of Lausanne, 1015 Lausanne, Switzerland"}]},{"given":"Kamiar","family":"Aminian","sequence":"additional","affiliation":[{"name":"Laboratory of Movement Analysis and Measurement, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne (EPFL), 1015 Lausanne, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2012,9,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"510","DOI":"10.1016\/j.jbiomech.2011.11.043","article-title":"3D kinematic and dynamic analysis of the front crawl tumble turn in elite male swimmers","volume":"45","author":"Puel","year":"2012","journal-title":"J. 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