To determine whether participation in youth soccer is associated with measurable short-term changes in the developing brain.
Approach:
Study Design: A prospective longitudinal cohort study involving 129 male adolescent athletes, including 82 soccer players and 47 noncontact-sport athletes, assessed over a competitive season.
Methods: Utilized magnetic resonance imaging, neurocognitive and behavioral testing, balance assessment, magnetic resonance spectroscopy, and plasma biomarkers.
Key Findings:
No statistically significant differences in cognition, behavior, balance, or brain structure/function between soccer players and noncontact-sport athletes.
Soccer players reported a mean of 939 headers during the season with substantial variation in heading exposure.
Higher preseason levels of total N-acetylaspartate, plasma neurofilament light chain, and glial fibrillary acidic protein in soccer players compared to controls.
No association between heading exposure and changes in any measured outcome.
Interpretation:
The findings provide short-term prospective data for physicians discussing youth soccer participation.
Limitations:
Observational, nonrandomized study design limits causal inference.
Potential underpowering due to lack of formal power calculation.
Self-reported heading exposure may bias exposure–outcome associations.
Conclusion:
Further studies are needed to explore long-term effects of repetitive head impacts.
