{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T12:02:15Z","timestamp":1777896135280,"version":"3.51.4"},"reference-count":50,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,17]],"date-time":"2021-11-17T00:00:00Z","timestamp":1637107200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Healthcare"],"abstract":"<jats:p>Training intensity monitoring is a daily practice in soccer which allows soccer academies to assess the efficacy of its developmental interventions and management strategies. The current systematic review\u2019s purpose is to: (1) identify and summarize studies that have examined external and internal training intensity monitoring, and to (2) provide references values for the main measures for young male soccer players. A systematic review of EBSCO, PubMed, Scielo, Scopus, SPORTDiscus, and Web of Science databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. From the 2404 studies initially identified, 8 were fully reviewed, and their outcome measures were extracted and analyzed. From them, the following range intervals were found for training: rated perceived exertion (RPE) 2.3\u20136.3 au; session-RPE, 156\u2013394 au; total distance, 3964.5\u20136500 m and; distance &gt;18 km\/h, 11.8\u2013250 m. Additionally, a general tendency to decrease the intensity in the day before the match was Found. This study allowed to provide reference values of professional young male players for the main internal and external measures. All together, they can be used by coaches, their staff, or practitioners in order to better adjust training intensity.<\/jats:p>","DOI":"10.3390\/healthcare9111567","type":"journal-article","created":{"date-parts":[[2021,11,17]],"date-time":"2021-11-17T21:32:07Z","timestamp":1637184727000},"page":"1567","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Reference Values for External and Internal Training Intensity Monitoring in Young Male Soccer Players: A Systematic Review"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6671-6229","authenticated-orcid":false,"given":"Rafael","family":"Oliveira","sequence":"first","affiliation":[{"name":"Sports Science School of Rio Maior, Polytechnic Institute of Santar\u00e9m, 2140-413 Rio Maior, Portugal"},{"name":"Research Center in Sport Sciences, Health Sciences and Human Development, 5001-801 Vila Real, Portugal"},{"name":"Life Quality Research Centre, 2140-413 Rio Maior, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4357-4269","authenticated-orcid":false,"given":"Jo\u00e3o Paulo","family":"Brito","sequence":"additional","affiliation":[{"name":"Sports Science School of Rio Maior, Polytechnic Institute of Santar\u00e9m, 2140-413 Rio Maior, Portugal"},{"name":"Research Center in Sport Sciences, Health Sciences and Human Development, 5001-801 Vila Real, Portugal"},{"name":"Life Quality Research Centre, 2140-413 Rio Maior, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7301-0619","authenticated-orcid":false,"given":"Adri\u00e1n","family":"Moreno-Villanueva","sequence":"additional","affiliation":[{"name":"Department of Physical Activity and Sport Sciences, International Excellence Campus \u201cMare Nostrum\u201d, Faculty of Sports Sciences, University of Murcia, 30720 San Javier, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7554-2718","authenticated-orcid":false,"given":"Matilde","family":"Nalha","sequence":"additional","affiliation":[{"name":"Sports Science School of Rio Maior, Polytechnic Institute of Santar\u00e9m, 2140-413 Rio Maior, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9849-0444","authenticated-orcid":false,"given":"Markel","family":"Rico-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Department of Didactics of Musical, Plastic and Corporal Expression, University of the Basque Country, UPV-EHU, 48940 Leioa, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9813-2842","authenticated-orcid":false,"given":"Filipe Manuel","family":"Clemente","sequence":"additional","affiliation":[{"name":"Escola Superior Desporto e Lazer, Instituto Polit\u00e9cnico de Viana do Castelo, Rua Escola Industrial e Comercial de Nun\u2019\u00c1lvares, 4900-347 Viana do Castelo, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Delega\u00e7\u00e3o da Covilh\u00e3, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1080\/24733938.2018.1427883","article-title":"Training load monitoring in elite English soccer: A comparison of practices and perceptions between coaches and practitioners","volume":"2","author":"Weston","year":"2018","journal-title":"Sci. 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