{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,28]],"date-time":"2025-11-28T17:00:21Z","timestamp":1764349221403,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,5]],"date-time":"2021-06-05T00:00:00Z","timestamp":1622851200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"This research was funded by a grant through the Instituto Portugu\u00eas do Desporto e Juventude, I. P. (CP\/362\/DD\/2016), to support sporting activity through the surveillance and monitoring system of sporting activity.","award":["CP\/362\/DD\/2016"],"award-info":[{"award-number":["CP\/362\/DD\/2016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Relative age is a phenomenon broadly studied in sport sciences. Youth sports participants born earlier in the selection year tend to present a maturational advantage over their peers. As it is also dependent on physical performance, older physical education students may also benefit from this effect in this school subject. The main goal of this manuscript was to determine whether the relative age effect is present within physical fitness outcomes of Portuguese children and adolescents. The physical\u2013aerobic fitness, strength, flexibility and body composition of 885 students (490 females and 395 males) were collected and compared by quarters of birth, segmented by gender and age groups (10\u201312; 12\u201314; 14\u201316 and 16\u201318 years). The results reveal a moderate to small effect in physical fitness outcomes, with a trend for children and adolescents born in the early part of the year to present higher performance levels. These differences were more evident in ages closer to the physical maturational onset (12\u201314 y) and more apparent in male students. This physical fitness advantage may lead to a biased assessment and development of students born earlier in the year.<\/jats:p>","DOI":"10.3390\/ijerph18116092","type":"journal-article","created":{"date-parts":[[2021,6,6]],"date-time":"2021-06-06T23:59:55Z","timestamp":1623023995000},"page":"6092","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Relative Age Effect in Physical Fitness of South Portugal Students between 10 and 18 Years Old"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9432-1950","authenticated-orcid":false,"given":"Hugo","family":"Folgado","sequence":"first","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre (CHRC), Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9009-5693","authenticated-orcid":false,"given":"Jorge","family":"Bravo","sequence":"additional","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre (CHRC), Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"}]},{"given":"Ana","family":"Quintas","sequence":"additional","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9753-8381","authenticated-orcid":false,"given":"Armando","family":"Raimundo","sequence":"additional","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre (CHRC), Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7874-4104","authenticated-orcid":false,"given":"Bruno","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre (CHRC), Universidade de \u00c9vora, Largo dos Colegiais, 7000-727 \u00c9vora, Portugal"},{"name":"Portugal Football School, Portuguese Football Federation, 1495-433 Oeiras, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1080\/17408980701711983","article-title":"Relative age effects on physical education attainment and school sport representation","volume":"13","author":"Cobley","year":"2008","journal-title":"Phys. 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