{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:16:27Z","timestamp":1760058987718,"version":"build-2065373602"},"reference-count":51,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,14]],"date-time":"2025-05-14T00:00:00Z","timestamp":1747180800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["10.54499\/UIDB\/05913\/2020","10.54499\/2021.08308.BD"],"award-info":[{"award-number":["10.54499\/UIDB\/05913\/2020","10.54499\/2021.08308.BD"]}]},{"name":"individual PhD","award":["10.54499\/UIDB\/05913\/2020","10.54499\/2021.08308.BD"],"award-info":[{"award-number":["10.54499\/UIDB\/05913\/2020","10.54499\/2021.08308.BD"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The most hydrodynamic swimming position occurs with the head submerged, highlighting the benefit of reduced breathing frequency for efficiency. This study aimed to characterize and compare kinematics between two breaststroke breathing patterns\u2014breathing every cycle and breathing every two cycles\u2014while also analyzing intra-cyclic velocity variation (dv) and fractal dimension. In the breathing every cycle pattern, each cycle included a breath. In the breathing every cycle pattern, swimmers breathed once per cycle. In the breathing every two cycles pattern, breathing occurred every second cycle, resulting in three types of cycles: breathing, non-breathing, and the breathing cycle following a non-breathing cycle. To ensure familiarity with the new breathing pattern, swimmers underwent a six-week intervention program. They then performed three maximal 25 m bouts in each breathing pattern. Kinematic data were collected using a dual-media optoelectronic system (Qualisys AB, Sweden), integrating underwater and dry-land camera recordings. The results showed minimal differences between the three cycle types. The non-breathing cycle had the shallowest and deepest head positions, the lowest horizontal head amplitude out of water, and the smallest vertical head amplitude. It also had the fastest maximum vertical velocity of the feet and maximum center of mass velocity in the swimming direction.<\/jats:p>","DOI":"10.3390\/s25103104","type":"journal-article","created":{"date-parts":[[2025,5,14]],"date-time":"2025-05-14T08:44:58Z","timestamp":1747212298000},"page":"3104","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Analyzing Breathing Patterns in the Breaststroke Technique Through Dual-Media Kinematics and Fractal Dimension"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6883-6686","authenticated-orcid":false,"given":"Miriam","family":"Alves","sequence":"first","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport (CIFI2D), 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP-UP), 4200-450 Porto, Portugal"},{"name":"Faculty of Sport, University of Porto, 4099-002 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4885-4924","authenticated-orcid":false,"given":"Pedro","family":"Fonseca","sequence":"additional","affiliation":[{"name":"Porto Biomechanics Laboratory (LABIOMEP-UP), 4200-450 Porto, Portugal"},{"name":"Faculty of Sport, University of Porto, 4099-002 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5720-1554","authenticated-orcid":false,"given":"Al\u00e9xia","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport (CIFI2D), 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP-UP), 4200-450 Porto, Portugal"},{"name":"Faculty of Sport, University of Porto, 4099-002 Porto, Portugal"}]},{"given":"Andr\u00e9 V.","family":"Brito","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport (CIFI2D), 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP-UP), 4200-450 Porto, Portugal"},{"name":"Faculty of Sport, University of Porto, 4099-002 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7071-2116","authenticated-orcid":false,"given":"Tiago M.","family":"Barbosa","sequence":"additional","affiliation":[{"name":"Department of Sport Sciences, Instituto Polit\u00e9cnico de Bragan\u00e7a, 5300-252 Bragan\u00e7a, Portugal"},{"name":"Research Centre for Active Living and Wellbeing (LiveWell), Instituto Polit\u00e9cnico de Bragan\u00e7a, 5300-253 Bragan\u00e7a, 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 (CIFI2D), 4200-450 Porto, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP-UP), 4200-450 Porto, Portugal"},{"name":"Faculty of Sport, University of Porto, 4099-002 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.2165\/00007256-199213010-00002","article-title":"Biomechanics of competitive front crawl swimming","volume":"13","author":"Toussaint","year":"1992","journal-title":"Sports Med."},{"key":"ref_2","first-page":"45","article-title":"The influence of drag on human locomotion in water","volume":"32","author":"Pendergast","year":"2005","journal-title":"Undersea Hyperb. 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