Acute effects of prismatic adaptation on penalty kick accuracy and postural control in young soccer players: A pilot study

Abstract

Background: Prismatic adaptation (PA) is a visuomotor technique using prismatic glasses that are capable of moving the visual field and to affect the excitability of certain brain areas. The aim of this pilot study was to explore potential acute effects of PA on penalty kick accuracy and postural control in youth soccer players.

Methods: In this randomized crossover study, seven young male soccer players performed three PA sessions (rightward PA, r-PA; leftward PA, l-PA; sham PA, s-PA) with a washout period of 1-week between them. Immediately before and after each PA session, penalty kick accuracy and postural control were assessed.

Results: We detected an increase in penalty kick accuracy following PA, regardless of the deviation side of the prismatic glasses (F_1,5 = 52.15; p = 0.08; ηp² = 0.981). In detail, our results showed an increase in the penalty kick accuracy toward the right target of the football goal following r-PA and toward the left target of the football goal following l-PA. We detected a significant effect on the sway path length (F_2,12 = 10.42; p = 0.002; ηp² = 0.635) and the sway average speed (F_2,12 = 9.17; p = 0.004; ηp² = 0.605) parameters in the stabilometric test with open eyes following PA, regardless of the deviation side of the prismatic glasses. In detail, our results showed a significant difference in both the stabilometric parameters (p = 0.016 and p = 0.009, respectively) only following l-PA.

Conclusion: The findings of this pilot study indicate that PA could positively affect penalty kick accuracy and postural control suggesting that PA could be used as a visual training technique in athletes.

Keywords: Body posture; Kinematic; Prismatic adaptation; Sport neuroscience; Sport performance; Visual training; Visuomotor performance; Visuomotor procedure.

Fig. 1

PA procedure consisted of pointing movements. Legend. Phase 1, pre-exposure (no prisms); phase 2, blind pre-exposure (no prisms); phase 3, early exposure (wearing prisms); phase 4, late exposure (i.e., adaptation - wearing prisms); phase 5, blind post-exposure (i.e., after-effect - no prisms).

Fig. 2

Setting for recording penalty kick sequences. Legend. The distance from the action camera (positioned in the center of the front edge of the penalty area) and the penalty spot was 9.15 m.

Fig. 3

Accuracy of the penalty kick after PA with right deviation. Legend. T0, pre-prismatic adaptation; T1, post-prismatic adaptation; right, right target of the football goal; left, left target of the football goal; center, center target of the football goal.

Fig. 4

Accuracy of the penalty kick after PA with left deviation. Legend. T0, pre-prismatic adaptation; T1, post-prismatic adaptation; right, right target of the football goal; left, left target of the football goal; center, center target of the football goal.

Fig. 5

Post-hoc analysis of the sway path length parameter after PA with left deviation. Legend. l-PA, left-prismatic adaptation; Pre-PA, pre-prismatic adaptation; Post-PA, post-prismatic adaptation.

Fig. 6

Post-hoc analysis of the sway average speed parameter after PA with left deviation. Legend. l-PA, left-prismatic adaptation; Pre-PA, pre-prismatic adaptation; Post-PA, post-prismatic adaptation.