{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,16]],"date-time":"2025-12-16T23:34:10Z","timestamp":1765928050252,"version":"3.48.0"},"reference-count":30,"publisher":"Georg Thieme Verlag KG","issue":"01","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int J Sports Med"],"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Soccer requires athletes to exhibit high levels of acceleration and speed, both of which are crucial for optimal performance. The acceleration\u2013speed (A\u2013S) profile is increasingly utilized to assess these sprinting capacities in soccer, providing in situ insights into an athlete\u2019s maximal theoretical acceleration (A0) and speed (S0). This study aimed to investigate the association of external load metrics with A0 and S0 across different age groups in elite academy soccer athletes. One hundred thirty-six athletes, ranging from under-14 to B-team, participated in the study. Training sessions and matches were monitored over a season using Global Navigation Satellite System (GNSS) technology to collect data on the A\u2013S profile and external load metrics. Stepwise regression analysis revealed a positive correlation, in several age groups (under-15, -17, -19, and -23 and B-team), between accumulation of sprint distance (Spr. Dist.) and an increased S0\n                                    (R\n               2: 0.30\u20130.52). However, no significant correlation was found between any external load metric and A0. These findings highlight the necessity of individualized training interventions and the inclusion of Spr. Dist. throughout the planning of the training load of young soccer athletes for the improvement of sprint capacity. It may also suggest that acceleration in youth soccer athletes may be influenced by other factors, such as strength training.<\/jats:p>","DOI":"10.1055\/a-2655-0650","type":"journal-article","created":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T22:54:33Z","timestamp":1755212073000},"page":"50-55","source":"Crossref","is-referenced-by-count":0,"title":["Associations Between Training Load and Acceleration\u2013Speed Profile in Youth Soccer Athletes"],"prefix":"10.1055","volume":"47","author":[{"given":"Pedro","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Medical and Performance Department, Sporting Clube Portugal, Lisboa, Portugal"}]},{"given":"Francisco","family":"Tavares","sequence":"additional","affiliation":[{"name":"Medical and Performance Department, Sporting Clube Portugal, Lisboa, Portugal"}]},{"given":"Nuno","family":"Loureiro","sequence":"additional","affiliation":[{"name":"Medical and Performance Department, Sporting Clube Portugal, Lisboa, Portugal"}]},{"given":"Ruben","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Medical and Performance Department, Sporting Clube Portugal, Lisboa, Portugal"}]},{"given":"Jo\u00e3o Pedro","family":"Ara\u00fajo","sequence":"additional","affiliation":[{"name":"Medical and Performance Department, Sporting Clube Portugal, Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2906-3665","authenticated-orcid":false,"given":"Joana F.","family":"Reis","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Fisiologia e Bioqu\u00edmica do Exerc\u00edcio, Universidade de Lisboa Faculdade de Motricidade Humana, Cruz Quebrada \u2013 Dafundo, Portugal"}]},{"given":"Jo\u00e3o R","family":"Vaz","sequence":"additional","affiliation":[{"name":"Egas Moniz Interdisciplinary Research Centre, Egas Moniz School of Health and Science Egas Moniz Center for Interdisciplinary Research, Caparica, 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