{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T09:04:24Z","timestamp":1785315864504,"version":"3.55.0"},"reference-count":35,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Funct. Morphol. Kinesiol.","JFMK"],"abstract":"<jats:p>Background: Pre-season physical monitoring may help coaches understand short-term changes in youth soccer players and examine whether physical indicators are associated with early squad inclusion. This study aimed to analyze changes in physical performance during the pre-season period and to examine whether pre- and post-assessment physical performance differed between squad-included and non-included under-15 male soccer players in the first five official matches of the main competition. Methods: Thirty-seven male outfield players were assessed using the Squat Jump (SJ), Countermovement Jump (CMJ), 20 m linear sprint (Sprint-20 m), 20 m change-in-direction test (COD-20m), and Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IRL1). Squad-included players were those listed in at least one of the first five official match reports, whereas non-included players were not listed in these reports but remained part of the broader under-15 program. Results: Significant increases were observed in SJ (+1.44 cm, p = 0.007), CMJ (+1.36 cm, p = 0.006), and COD-20m (+0.38 km\u00b7h\u22121, p = 0.002), whereas Sprint-20 m and Yo-Yo IRL1 did not change significantly. Fourteen players were squad-included and 23 were non-included. Squad-included players presented higher pre-assessment values for SJ, CMJ, COD-20m, and the exploratory composite physical score, and higher post-assessment values for SJ, CMJ, Sprint-20 m, COD-20m, and the exploratory composite physical score. The largest between-group difference was observed for post-assessment COD-20m (14.19 \u00b1 0.49 vs. 13.40 \u00b1 0.74 km\u00b7h\u22121, p &lt; 0.001, d = 1.25). Conclusions: Early squad inclusion was associated with higher absolute physical performance, particularly post-assessment COD-20m, whereas the magnitude of pre-to-post changes was not clearly associated with squad inclusion.<\/jats:p>","DOI":"10.3390\/jfmk11030300","type":"journal-article","created":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T08:16:52Z","timestamp":1785313012000},"page":"300","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pre-Season Changes in Physical Performance and Early Competitive Squad Inclusion in Under-15 Male Soccer Players"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7516-2982","authenticated-orcid":false,"given":"Artur Avelino Birk","family":"Preissler","sequence":"first","affiliation":[{"name":"Educa\u00e7\u00e3o F\u00edsica, Faculdade SOGIPA, Porto Alegre 90240-485, Brazil"},{"name":"School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre 90690-200, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9813-2842","authenticated-orcid":false,"given":"Filipe Manuel","family":"Clemente","sequence":"additional","affiliation":[{"name":"Applied Research Institute (i2A), Polytechnic University of Coimbra, 3045-093 Coimbra, Portugal"},{"name":"The Sport Physical Activity and Health Research & Innovation Center, 3045-093 Coimbra, Portugal"},{"name":"Department of Biomechanics and Sport Engineering, Gdansk University of Physical Education and Sport, 80-336 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3013-1760","authenticated-orcid":false,"given":"J\u00falio Brugnara","family":"Mello","sequence":"additional","affiliation":[{"name":"Grupo de Investigaci\u00f3n en Adaptaciones Musculoesquel\u00e9ticas al Entrenamiento, Physical Education School, Pontificia Universidad Cat\u00f3lica de Valpara\u00edso, Valpara\u00edso 2340025, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1772-1272","authenticated-orcid":false,"given":"Ana Filipa","family":"Silva","sequence":"additional","affiliation":[{"name":"Faculty of Sport Sciences and Physical Education, University of Coimbra, 3040-256 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3380-864X","authenticated-orcid":false,"given":"Rui Miguel","family":"Silva","sequence":"additional","affiliation":[{"name":"Escola Superior de Desporto e Lazer, Instituto Polit\u00e9cnico de Viana do Castelo, 4900-347 Viana do Castelo, Portugal"},{"name":"The Sport Physical Activity and Health Research & Innovation Center, 4900-347 Viana do Castelo, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6875-7593","authenticated-orcid":false,"given":"Pedro","family":"Schons","sequence":"additional","affiliation":[{"name":"Educa\u00e7\u00e3o F\u00edsica, Faculdade SOGIPA, Porto Alegre 90240-485, Brazil"},{"name":"School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre 90690-200, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1007\/s40279-017-0851-7","article-title":"Talent Identification and Development in Male Football: A Systematic Review","volume":"48","author":"Sarmento","year":"2018","journal-title":"Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1719","DOI":"10.1080\/02640414.2012.731515","article-title":"Talent Identification in Youth Soccer","volume":"30","author":"Unnithan","year":"2012","journal-title":"J. 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