Data from: Effects of repetitive head impacts from a single season on the cognitive functioning of youth male soccer players

Repetitive head impacts have long-lasting negative effects on the
cognition of athletes. For example, repetitive head impacts accumulated by
adult professional soccer players throughout their careers result in
long-term negative consequences on cognition. However, these effects on
youth soccer players have not been extensively studied and need to be
further evaluated. The purposes of this study were to quantify head impact
exposure in youth elite soccer and to examine the effects of repetitive
head impacts on the cognitive function of youth male soccer players. A
prospective cohort study of a single boys U13 soccer team of 18 players
(12.9 ± 0.2 years of age) was completed throughout a single soccer season
(five months in duration). Head impact frequency data were recorded using
impact monitoring mouthguards worn during practices and games and
subsequently video-verified. Cognitive function was assessed using
cognitive-motor integration (CMI) tasks conducted before the first season
game, every subsequent four weeks, and after the last game. Peak path
velocity, absolute error, reaction time, full path movement time, and the
number of direction reversals were CMI task outcome measures. Over a
single soccer season, 1089 head impacts occurred with more head impacts
occurring in practices (62.7%) than in games (37.3%). Midfielders
experienced the most head impacts during practices (53.6% of practice
impacts), and defenders experienced the most head impacts during games
(47.8% of game impacts). Repetitive head impact exposure by position was
associated with significant decreases in absolute error (p<0.001),
increases in peak velocity (p<0.001), and increases in reaction
time (p<0.001). Repetitive head impacts within a single soccer
season were associated with measurable declines in some aspects of youth
soccer players’ cognitive function. Therefore, coaches should aim to
reduce the number of head impacts experienced by male youth soccer players
with a specific focus on reducing head impact exposure during practices.