{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T19:50:40Z","timestamp":1788465040256,"version":"build-2803163510"},"reference-count":27,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T00:00:00Z","timestamp":1759449600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n (AEI), Spain","doi-asserted-by":"publisher","award":["PID2020-112658RB-I00"],"award-info":[{"award-number":["PID2020-112658RB-I00"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011033","name":"Agencia Estatal de Investigaci\u00f3n (AEI), Spain","doi-asserted-by":"publisher","award":["PID2023-146540OB-C41"],"award-info":[{"award-number":["PID2023-146540OB-C41"]}],"id":[{"id":"10.13039\/501100011033","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Consejo Superior de Deportes (CSD), Spain","award":["INNOVA ATHLETICS 2030"],"award-info":[{"award-number":["INNOVA ATHLETICS 2030"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Sensors"],"abstract":"<jats:p>Photogrammetry applied to sports provides precise data on athlete positions and time instants, especially with digital motion capture systems. However, detecting and identifying specific events in athletic movements such as discus throwing can be challenging when using only images. For example, with high-speed video, it is difficult to pinpoint the exact frame when events like foot touchdown or takeoff occur, as contact between shoe and ground may span several frames. Inertial measurement units (IMUs) can detect maxima and minima in linear accelerations and angular velocities, helping to accurately determine these specific events in throwing movements. As a result, comparing photogrammetry data with IMU data becomes challenging because of the differences in the methods used to detect events. Even if comparisons can be made with IMU data from other sports researchers, variations in methodologies can invalidate the comparison. To address this, the paper proposes a simple methodology for detecting the five phases of a discus throw using three IMUs located on the thrower\u2019s wrist and on the instep or ankle of the feet. Experiments with three elite male discus throwers are conducted and the results are compared with existing data in the literature. The findings demonstrate that the proposed methodology is effective (100% of phases detected in the experiments without false positives) and reliable (results validated with professional coaches), offering a practical and time- and cost-effective solution for accurately detecting key moments in athletic movements.<\/jats:p>","DOI":"10.3390\/s25196095","type":"journal-article","created":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T07:57:27Z","timestamp":1759478247000},"page":"6095","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Use of Inertial Measurement Units for Detection of the Support Phases in Discus Throwing"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6702-3771","authenticated-orcid":false,"given":"Jos\u00e9","family":"S\u00e1nchez-Moreno","sequence":"first","affiliation":[{"name":"Department of Computer Science and Automatic Control, Universidad Nacional de Educaci\u00f3n a Distancia, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0264-3419","authenticated-orcid":false,"given":"David","family":"Moreno-Salinas","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Automatic Control, Universidad Nacional de Educaci\u00f3n a Distancia, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Carlos","family":"\u00c1lvarez-Ortiz","sequence":"additional","affiliation":[{"name":"Real Federaci\u00f3n Espa\u00f1ola de Atletismo, 28223 Pozuelo de Alarc\u00f3n, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1075","DOI":"10.1080\/02640414.2011.587018","article-title":"Evolution and revolution: Gauging the impact of technological and technical innovation on Olympic performance","volume":"30","author":"Balmer","year":"2021","journal-title":"J. Sports Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"291","DOI":"10.1080\/16138171.2017.1421504","article-title":"Sport innovation: Developing a typology","volume":"14","year":"2017","journal-title":"Eur. J. Sport Soc."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1123\/ijsb.1.2.131","article-title":"Kinematic analysis of Olympic discus throwers","volume":"1","author":"Gregor","year":"1985","journal-title":"Int. J. Sport Biomech."},{"key":"ref_4","unstructured":"Bartonietz, K., and Borgstrom, A. (2025, September 20). Biomechanics of the Throwing Events: An Introduction to a Simplified Way of Analyzing with Normal Video Equipment. Available online: https:\/\/www.speerschule.ch\/docs\/doc_bartonietz-goteborg95.pdf."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1080\/02640419508732220","article-title":"Critical characteristics of technique in throwing the discus","volume":"13","author":"Hay","year":"1995","journal-title":"J. Sports Sci."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Chen, C.-F., Wu, H.-J., Yang, Z.-S., Chen, H., and Peng, H.-T. (2021). Motion Analysis for Jumping Discus Throwing Correction. Int. J. Environ. Res. Public Health, 18.","DOI":"10.3390\/ijerph182413414"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Wang, L., Hao, L., and Zhang, B. (2022). Kinematic diagnosis of throwing motion of the Chinese elite female discus athletes who are preparing for the Tokyo Olympic games. J. Environ. Public Health, 2022.","DOI":"10.1155\/2022\/3334225"},{"key":"ref_8","unstructured":"K\u00f6ykk\u00e4, M., Vohlakari, K., Joutsen, T., V\u00e4nttinen, T., Piironen, P., Rantalainen, T., and Cronin, N. (2022). Markerless video-based estimation of 3D approach velocity in the javelin throw. ISBS Proc. Arch., 40, Available online: https:\/\/commons.nmu.edu\/isbs\/vol40\/iss1\/85."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Wang, Y., Shan, G., Li, H., and Wang, L. (2023). A wearable-sensor system with AI technology for real-time biomechanical feedback training in hammer throw. Sensors, 23.","DOI":"10.3390\/s23010425"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"985","DOI":"10.1177\/1747954118778664","article-title":"Use of inertial measurement units for measuring torso and pelvis orientation, and shoulder\u2013pelvis separation angle in the discus throw","volume":"13","author":"Brice","year":"2018","journal-title":"Int. J. Sports Sci. Coach."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Tiedemann, S., Menrad, T., and Witte, K. (2022). Application of inertial sensors to identify performance-relevant parameters in Olympic hammer throw. Int. J. Environ. Res. Public Health, 19.","DOI":"10.3390\/ijerph19095402"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1007\/s40279-022-01760-6","article-title":"Wearables for running gait analysis: A systematic review","volume":"53","author":"Mason","year":"2023","journal-title":"Sports Med."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Liu, J., Wang, J., Zhao, Y., Zhao, Q., Li, J., and Dongxue, C. (2011, January 16\u201317). Research on the application of the three-dimensional information collection system of digital discus to the throwing technique of the discus throwers. Proceedings of the 2001 International Conference on Future Computer Science and Education, Hong Kong, China.","DOI":"10.1109\/ICFCSE.2011.56"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1007\/s12283-016-0194-x","article-title":"Augmented inertial measurements for analysis of javelin throwing mechanics","volume":"19","author":"Nieminen","year":"2016","journal-title":"Sports Eng."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Moreno-Salinas, D., S\u00e1nchez-Moreno, J., \u00c1lvarez, J.C., and Revuelta, C. (2024, January 5\u20137). Sistema para la mejora del entrenamiento del lanzamiento de disco. Proceedings of the XLV Jornadas de Autom\u00e1tica, Madrid, Spain.","DOI":"10.17979\/ja-cea.2024.45.10615"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Camomilla, V., Bergamini, E., Fantozzi, S., and Vannozzi, G. (2018). Trends Supporting the In-Field Use of Wearable Inertial Sensors for Sport Performance Evaluation: A Systematic Review. Sensor, 18.","DOI":"10.3390\/s18030873"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Hindle, B.R., Keogh, J.W.L., and Lorimer, A.V. (2021). Inertial-based human motion capture: A technical summary of current processing methodologies for spatiotemporal and kinematic measures. Appl. Bionics Biomech., 2021.","DOI":"10.1155\/2021\/6628320"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1853","DOI":"10.1080\/14763141.2021.1990383","article-title":"Validity of inertial measurement units for tracking human motion: A systematic review","volume":"23","author":"Ghattas","year":"2021","journal-title":"Sports Biomech."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Witte, K., and Tiedemann, S. (2024). Inertial Sensing in Sports, Springer Spektrum.","DOI":"10.1007\/978-3-662-68703-1_6"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1080\/14763140701841399","article-title":"The relationship between discus throwing performance and combinations of selected technical parameters","volume":"7","author":"Leigh","year":"2008","journal-title":"Sports Biomech."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Navarro-Iribarne, J.F., Moreno-Salinas, D., and S\u00e1nchez-Moreno, J. (2022). Low-cost portable system for measurement and representation of 3D kinematic parameters in sport monitoring: Discus throwing as a case study. Sensor, 22.","DOI":"10.3390\/s22239408"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1080\/02640419208729944","article-title":"The biomechanics of the discus throw: A review","volume":"10","author":"Bartlett","year":"1992","journal-title":"J. Sports Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"624","DOI":"10.1080\/14763141.2021.1880619","article-title":"Rotation of the thrower-discus system and performance in discus throwing","volume":"23","author":"Liu","year":"2021","journal-title":"Sports Biomech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"826","DOI":"10.4100\/jhse.2012.74.10","article-title":"Temporal analysis of elite men\u2019s discus throwing technique","volume":"7","author":"Panoutsakopoulos","year":"2012","journal-title":"J. Hum. Sport Exerc."},{"key":"ref_25","unstructured":"Dapena, J., and Anderst, W.J. (2025, September 15). Discus Throw Report 01-1997 (Men). Available online: https:\/\/www.scribd.com\/document\/357553241\/Discus-Throw-Report-01-1997-Men."},{"key":"ref_26","unstructured":"(2025, February 01). Movella. Available online: https:\/\/www.movella.com\/products\/wearables\/movella-dot."},{"key":"ref_27","first-page":"34","article-title":"Generating speed. Momentum analysis in discus throwing","volume":"15","author":"Maheras","year":"2022","journal-title":"Tech. Track Field Cross Country"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/25\/19\/6095\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T07:59:58Z","timestamp":1759478398000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/25\/19\/6095"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,10,3]]},"references-count":27,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2025,10]]}},"alternative-id":["s25196095"],"URL":"https:\/\/doi.org\/10.3390\/s25196095","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,10,3]]}}}