doi:10.1111/sms.70253engConesa-Milian, EnricBatalla-Gavaldà, AbrahamHernández-González, VicençLópez-Laval, IsaacCorbi, FrancescCirer-Sastre, RafelLegaz-Arrese, AlejandroReverter-Masia, JoaquinHigh‐sensitivity cardiac troponin t release after the 20‐m shuttle run test in 733 healthy children and adolescentsART-2026-148646This study aimed to assess the effect of exercise on high-sensitivity cardiac troponin T (hs-cTnT) concentrations in children and adolescents and to examine whether sex, maturational status, anthropometric characteristics, cardiorespiratory fitness, and physical activity influence the hs-cTnT response. In this trial 733 participants completed the 20-m shuttle run test. Venous blood samples were collected at rest and 3h postexercise to determine hs-cTnT concentrations. We included 296 girls and 437 boys (12.2±1.7 years; 40% girls). At baseline, 61% of participants had hs-cTnT values below the limit of detection (LoD), and 2.5% exceeded the upper reference limit (URL). Postexercise, 36% remained below LoD, while 7.5% exceeded the URL. Overall, hs-cTnT increased from baseline to 3h postexercise in 56.2% of participants. Linear mixed-effects models showed a significant main effect of time (β=−0.42, 95% CI 0.35–0.49; p<0.01) and no main effect of sex (p=0.85), although a small but significant time×sex interaction was observed (β=−0.11, 95% CI −0.20 to −0.02; p=0.021), indicating a slightly greater exercise-induced increase in girls. Additional significant time×covariate interactions were identified for maturational, anthropometric, and fitness-related variables. However, these factors together explained only a small proportion of the overall variability in hs-cTnT response. Consequently, the 20-m shuttle run test induces a significant increase in hs-cTnT concentrations in children and adolescents. Exercise-induced hs-cTnT release is common but highly heterogeneous, and is only partly explained by sex, maturational, anthropometric, and fitness-related factors, suggesting an important contribution of individual-specific determinants not captured by conventional variables.2026http://zaguan.unizar.es/record/17009410.1111/sms.70253http://zaguan.unizar.es/record/170094oai:zaguan.unizar.es:170094info:eu-repo/grantAgreement/ES/AEI/PID2020-117932RB-I00Scandinavian Journal of Medicine and Science in Sports 36, 3 (2026), [9 pp.]by-nc-ndhttps://creativecommons.org/licenses/by-nc-nd/4.0/deed.esinfo:eu-repo/semantics/openAccess