Effects of Different Header Types on Neurocognitive and Vestibular Performance in Youth Soccer Players

Repetitive head impacts due to heading in soccer may bear the potential to induce brain changes. To investigate how brain development is affected by heading, effects of heading exposure on neurocognitive and vestibular performance in adolescent soccer players were prospectively examined.

In this longitudinal cohort study, male and female high-level youth soccer players of different ages were enrolled in two seasons. Age-matched athletes of other ball sports were included as controls. Before and after each season, neurocognitive performance (six domain scores), vestibulo-ocular reflex, dynamic visual acuity, and postural control (sway velocity) were objectively assessed in all athletes. Every soccer training and match during the observation period was videotaped to analyze individual heading exposure. Associations between heading frequency (total, in duels, >20-m flight distance) and pre- to post-changes were investigated via the Spearman correlation.

A total of 103 soccer and 51 control athletes (9-19 yr) participated. Neurocognitive scores and sway velocity significantly improved in each season in soccer and control athletes. There were no associations between total heading numbers and changes in any parameter. Over the first season, the more headers played in duels ( r = -0.255; 95% confidence interval (CI), -0.474 to -0.006; P = 0.04) and from >20-m distance ( r = -0.299; 95% CI, -0.510 to -0.055; P = 0.02), the less psychomotor speed improvement occurred. In the second season, improvements in reaction time were significantly smaller with higher numbers of headers played in duels ( r = 0.375; 95% CI, 0.043 to 0.632; P = 0.02) and from >20-m distance ( r = 0.359; 95% CI, 0.025 to 0.621; P = 0.03).

Potential high-impact headers may have affected neurocognitive improvements, exhibiting small to moderate effects. Therefore, more high-impact headers may be more important to consider than solely the overall heading exposure in discussions about adverse effects in youth soccer.