{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T04:11:04Z","timestamp":1768623064405,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,9]],"date-time":"2024-01-09T00:00:00Z","timestamp":1704758400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100018165","name":"Chandrakasem Rajabhat University","doi-asserted-by":"publisher","award":["001\/2562"],"award-info":[{"award-number":["001\/2562"]}],"id":[{"id":"10.13039\/100018165","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100018165","name":"Chandrakasem Rajabhat University","doi-asserted-by":"publisher","award":["UIDB\/00617\/2020"],"award-info":[{"award-number":["UIDB\/00617\/2020"]}],"id":[{"id":"10.13039\/100018165","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100018165","name":"Chandrakasem Rajabhat University","doi-asserted-by":"publisher","award":["UIDP\/00617\/2020"],"award-info":[{"award-number":["UIDP\/00617\/2020"]}],"id":[{"id":"10.13039\/100018165","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100018165","name":"Chandrakasem Rajabhat University","doi-asserted-by":"publisher","award":["LA\/P\/0064\/2020"],"award-info":[{"award-number":["LA\/P\/0064\/2020"]}],"id":[{"id":"10.13039\/100018165","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Center in Physical Activity, Health, and Leisure\u2014CIAFEL\u2014Faculty of Sports (FADEUP), University of Porto, Portuguese Foundation for Science and Technology","award":["001\/2562"],"award-info":[{"award-number":["001\/2562"]}]},{"name":"Research Center in Physical Activity, Health, and Leisure\u2014CIAFEL\u2014Faculty of Sports (FADEUP), University of Porto, Portuguese Foundation for Science and Technology","award":["UIDB\/00617\/2020"],"award-info":[{"award-number":["UIDB\/00617\/2020"]}]},{"name":"Research Center in Physical Activity, Health, and Leisure\u2014CIAFEL\u2014Faculty of Sports (FADEUP), University of Porto, Portuguese Foundation for Science and Technology","award":["UIDP\/00617\/2020"],"award-info":[{"award-number":["UIDP\/00617\/2020"]}]},{"name":"Research Center in Physical Activity, Health, and Leisure\u2014CIAFEL\u2014Faculty of Sports (FADEUP), University of Porto, Portuguese Foundation for Science and Technology","award":["LA\/P\/0064\/2020"],"award-info":[{"award-number":["LA\/P\/0064\/2020"]}]},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR)","award":["001\/2562"],"award-info":[{"award-number":["001\/2562"]}]},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR)","award":["UIDB\/00617\/2020"],"award-info":[{"award-number":["UIDB\/00617\/2020"]}]},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR)","award":["UIDP\/00617\/2020"],"award-info":[{"award-number":["UIDP\/00617\/2020"]}]},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR)","award":["LA\/P\/0064\/2020"],"award-info":[{"award-number":["LA\/P\/0064\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sports"],"abstract":"<jats:p>This study aimed to quantify the relationships among internal training load, wellness, physiological, isokinetic profile, and technical performance and assessed changes before and after a six-week pre-season structured combining physical fitness, small-sided-game and skill-based training program in young soccer players. Forty-five national-level young male soccer players (16.8 \u00b1 0.9 years) were evaluated. There were no significant correlations between the wellness index and the physiological, isokinetic, or specific soccer skill parameters. Moderate correlations were observed between fatigue and stress (r = 0.47, moderate, p &lt; 0.01), fatigue and average muscle soreness (r = 0.38, moderate, p = 0.01), and a large correlation between average stress and muscle soreness (r = 0.53, large, p &lt; 0.01) were presented. All physiological, isokinetic, and technical parameters improved after a six-week pre-season training program (0.1 to \u221261.0%). Significant alterations in the physiological domain were observed after a six-week period, particularly in the fatigue index of the Bangsbo sprint test, YO-YO IR1 performance, and YO-YO peak La- (p &lt; 0.01; \u221261.0%, 25.3%, and \u221219.8%, respectively). As such, the implementation of structured training and the monitoring of stress responses can lead to appropriate adaptation and balancing in the psychological and physical well-being of young national-level soccer players, particularly in the pre-season period.<\/jats:p>","DOI":"10.3390\/sports12010023","type":"journal-article","created":{"date-parts":[[2024,1,9]],"date-time":"2024-01-09T03:36:58Z","timestamp":1704771418000},"page":"23","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Follow-Up Weekly Training Distribution and Accumulated Internal Load Effects on Young Football Players\u2019 Well-Being, Physical Fitness, and Technical Performance"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0921-7914","authenticated-orcid":false,"given":"Yutthana","family":"Riansoi","sequence":"first","affiliation":[{"name":"Faculty of Science, Chandrakasem Rajabhat University, Bangkok 10900, Thailand"}]},{"given":"Nuntapol","family":"Tongnillpant","sequence":"additional","affiliation":[{"name":"Sports Science Centre, Sports Authority of Thailand, Bangkok 10900, Thailand"}]},{"given":"Sakdarin","family":"Thammawong","sequence":"additional","affiliation":[{"name":"Faculty of Sport Science and Health, Thailand National Sports University, Udonthani Campus, Udonthani 12110, Thailand"}]},{"given":"Jo\u00e3o","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"Center of Research, Education, Innovation and Intervention in Sports (CIFI2D), Faculty of Sports, University of Porto, 4099-002 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0494-0000","authenticated-orcid":false,"given":"Rodrigo","family":"Zacca","sequence":"additional","affiliation":[{"name":"Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto (FADEUP), 4099-002 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2605-4181","authenticated-orcid":false,"given":"Phornpot","family":"Chainok","sequence":"additional","affiliation":[{"name":"Faculty of Sports Science, Burapha University, Chonburi 20131, Thailand"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1123\/ijspp.2018-0935","article-title":"Internal and external training load: 15 years on","volume":"14","author":"Impellizzeri","year":"2019","journal-title":"Int. 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