{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T15:59:59Z","timestamp":1778169599370,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,12]],"date-time":"2022-02-12T00:00:00Z","timestamp":1644624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Quantitative evaluation of synergic action among the different body segments is fundamental to swimming performance. The aim of the present study was to develop an easy-to-use tool for stroke-by-stroke evaluation of a swimmer\u2019s integrated timing of stroking, kicking, and breathing. Twelve swimmers were evaluated during one trial of 100 m front-crawl swimming at self-selected speed. Five three-axial inertial sensors were mounted on the head, wrists, and ankles. Algorithms for the wrist entry into the water, the lower limb beat during the downward action, and the exit\/entry of the face from\/into the water were developed. Temporal events identified by video-based technique, using one sagittal moving camera, were assumed as the gold standard. The performance was evaluated in terms of the root-mean-square error, 90th percentile of absolute error, coefficient of variation, Bland\u2013Altman plots, and correlation analysis. Results of all temporal events showed high agreement with the gold standard, confirmed by a root-mean-square error of less than 0.05 s for absolute temporal parameters and less than 0.7% for the percentages of the stroke cycle duration, and with correlation coefficients higher than 0.856. The protocol proposed was not only accurate and reliable, but also user-friendly and as unobtrusive as possible for the swimmer, allowing a stroke-by-stroke analysis during the training session.<\/jats:p>","DOI":"10.3390\/s22041419","type":"journal-article","created":{"date-parts":[[2022,2,13]],"date-time":"2022-02-13T20:34:45Z","timestamp":1644784485000},"page":"1419","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Integrated Timing of Stroking, Breathing, and Kicking in Front-Crawl Swimming: A Novel Stroke-by-Stroke Approach Using Wearable Inertial Sensors"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0660-7204","authenticated-orcid":false,"given":"Silvia","family":"Fantozzi","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering \u201cGuglielmo Marconi\u201d, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy"},{"name":"Health Sciences and Technologies-Interdepartmental Centre for Industrial Research, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vittorio","family":"Coloretti","sequence":"additional","affiliation":[{"name":"Department of Electrical, Electronic, and Information Engineering \u201cGuglielmo Marconi\u201d, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1927-7478","authenticated-orcid":false,"given":"Maria Francesca","family":"Piacentini","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3231-5897","authenticated-orcid":false,"given":"Claudio","family":"Quagliarotti","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0053-397X","authenticated-orcid":false,"given":"Sandro","family":"Bartolomei","sequence":"additional","affiliation":[{"name":"Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6322-7761","authenticated-orcid":false,"given":"Giorgio","family":"Gatta","sequence":"additional","affiliation":[{"name":"Department for Life Quality Studies, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1518-8221","authenticated-orcid":false,"given":"Matteo","family":"Cortesi","sequence":"additional","affiliation":[{"name":"Department for Life Quality Studies, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1007\/s00421-019-04270-y","article-title":"The Energy Cost of Swimming and Its Determinants","volume":"120","author":"Zamparo","year":"2020","journal-title":"Eur. 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