{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:28:46Z","timestamp":1760149726152,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,7]],"date-time":"2023-09-07T00:00:00Z","timestamp":1694044800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002322","name":"Coordination for the Improvement of Higher Education Personnel Foundation\u2014CAPES","doi-asserted-by":"publisher","award":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"],"award-info":[{"award-number":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"the Foundation for Science and Technology\u2014FCT","doi-asserted-by":"publisher","award":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"],"award-info":[{"award-number":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"CAPES-FCT","award":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"],"award-info":[{"award-number":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"]}]},{"name":"SANTADER","award":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"],"award-info":[{"award-number":["BEX 0761\/12-5\/2012-2015","EXPL\/DTP-DES\/2481\/2013-FCOMP-01-0124-FEDER-041981","99999.008578\/2014-01","PP\/IJUP2011\/123"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The analysis of the external forces of swimming starts has revealed how swimmers propel themselves out of the block, but data should be properly interpreted to fully understand force-generation mechanisms. This study aimed to assess horizontal and vertical forces in the backstroke start based on swimmers\u2019 structural and propulsive actions. Firstly, a simulated structural force was estimated by two transient backstroke-start inter-segmental realistic body positions: a maximally tucked position and an extended one (just before the hands-off and the take-off, respectively). Secondly, 10 competitive backstroke swimmers performed four 15 m maximal backstroke starts with the external forces estimated. Thirdly, the simulated structural force was subtracted from raw horizontal and vertical force data, measured between hands-off and take-off instants, resulting in the propulsive forces. The application of the algorithm has evidenced that backstrokers\u2019 horizontal and vertical simulated-structural-force components contributed to ~40% of total force during start propulsion (~0.2\u20130.12 s before the take-off), followed by the propulsive horizontal force increment and a progressive vertical component reduction (~0.05 s) with ~20\u00b0 take-off angle. Based on these findings, researchers and coaches can better guide swimmers as to the proper mechanical strategies to achieve effectiveness in the backstroke start, and to improve direct transfer of resistance training programs.<\/jats:p>","DOI":"10.3390\/s23187723","type":"journal-article","created":{"date-parts":[[2023,9,7]],"date-time":"2023-09-07T10:09:50Z","timestamp":1694081390000},"page":"7723","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Swimmers\u2019 Effective Actions during the Backstroke Start Technique"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7710-9843","authenticated-orcid":false,"given":"Karla","family":"de Jesus","sequence":"first","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Human Studies Development Laboratory, Faculty of Physical Education and Physiotherapy, Federal University of Amazonas, Manaus 69077-000, AM, Brazil"}]},{"given":"Kelly","family":"de Jesus","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Human Studies Development Laboratory, Faculty of Physical Education and Physiotherapy, Federal University of Amazonas, Manaus 69077-000, AM, Brazil"}]},{"given":"Lu\u00eds","family":"Mour\u00e3o","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Polytechnic Institute of Porto School of Engineering, 4249-015 Porto, Portugal"}]},{"given":"H\u00e9lio","family":"Roesler","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Aquatic Biomechanics Research Laboratory, Health and Sports Science Centre, University of the State of Santa Catarina, Florian\u00f3polis 88080-350, SC, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5811-0443","authenticated-orcid":false,"given":"Ricardo J.","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6347-9608","authenticated-orcid":false,"given":"M\u00e1rio A. P.","family":"Vaz","sequence":"additional","affiliation":[{"name":"Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal"},{"name":"Institute of Mechanical Engineering and Industrial Management, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4109-2939","authenticated-orcid":false,"given":"Jo\u00e3o Paulo","family":"Vilas-Boas","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5332-5974","authenticated-orcid":false,"given":"Leandro J.","family":"Machado","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"468","DOI":"10.1080\/02640414.2012.736631","article-title":"The categorisation of swimming start performance with reference to force generation on the main block and footrest components of the Omega OSB11 start blocks","volume":"31","author":"Slawson","year":"2013","journal-title":"J. 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