High-Sensitivity Cardiac Troponin T Release After the 20-m Shuttle Run Test in 733 Healthy Children and Adolescents.

The 20-m shuttle run test caused a significant increase in hs-cTnT concentrations from baseline to 3 hours postexercise in the majority of participants.

• 733 participants completed the 20-m shuttle run test (296 girls and 437 boys; 12.2 ± 1.7 years; 40% girls)
• Overall, hs-cTnT increased from baseline to 3 h 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)
• Venous blood samples were collected at rest and 3 h postexercise to determine hs-cTnT concentrations

At baseline, the majority of participants had hs-cTnT values below the limit of detection, while postexercise the proportion below the limit of detection decreased substantially.

• At baseline, 61% of participants had hs-cTnT values below the limit of detection (LoD)
• At baseline, 2.5% of participants exceeded the upper reference limit (URL)
• Postexercise, 36% remained below the LoD
• Postexercise, 7.5% exceeded the URL, representing a threefold increase compared to baseline

There was no main effect of sex on hs-cTnT concentrations, but a small but significant time × sex interaction indicated a slightly greater exercise-induced increase in girls.

• No main effect of sex was observed (p = 0.85)
• A small but significant time × sex interaction was identified (β = -0.11, 95% CI -0.20 to -0.02; p = 0.021)
• The interaction indicated a slightly greater exercise-induced increase in hs-cTnT in girls compared to boys

Maturational status, anthropometric characteristics, and fitness-related variables showed significant time × covariate interactions with hs-cTnT response but together explained only a small proportion of overall variability.

• Additional significant time × covariate interactions were identified for maturational, anthropometric, and fitness-related variables
• These factors together explained only a small proportion of the overall variability in hs-cTnT response
• The findings suggest an important contribution of individual-specific determinants not captured by conventional variables
• Cardiorespiratory fitness and physical activity levels were among the covariates examined

Exercise-induced hs-cTnT release in children and adolescents is a common but highly heterogeneous phenomenon.

• The study included 733 healthy children and adolescents, representing a large sample for this population
• The heterogeneity of the hs-cTnT response was only partly explained by sex, maturational, anthropometric, and fitness-related factors
• The authors conclude that individual-specific determinants not captured by conventional variables make an important contribution to hs-cTnT response variability
• The 20-m shuttle run test is a maximal incremental field test commonly used to estimate cardiorespiratory fitness in youth