Our data demonstrate that intraocular pressure (IOP) is sensitive to anxiety manipulation in sport scenarios, specifically in a basketball free throw task. The present outcomes may be of special relevance because of its practical advantages for the objective control of athletes' anxiety levels.
Athletes experience high levels of anxiety during sport competition, and IOP has demonstrated to reflect autonomous nervous system changes during mentally demanding situations. We tested whether different levels of induced anxiety during basketball free throw shooting alter IOP.
We followed a repeated-measures design to test the effects of anxiety-induced manipulation during basketball free throw shooting on IOP, shooting performance, and perceived anxiety. Eighteen amateur basketball players performed three experimental sessions consisting of 100 free throws each. However, we gave three different instructions to participants regarding the score assigned to each free throw, allowing us to manipulate the level of induced anxiety (low, medium, and high).
Confirming a successful anxiety manipulation, basketball players reported more perceived anxiety with higher levels of induced anxiety (P < .001, η2 = 0.37). Our data show that higher levels of induced anxiety provoke an acute IOP rise (P < .001, η2 = 0.44), with the low-, medium-, and high-anxiety–induced conditions promoting an average IOP rise of 0.21, 1.63, and 18.46%, respectively. Also, there was a linear IOP rise over time in the high-anxiety–induced condition (r = 0.82). Nevertheless, we found no effect of anxiety-induced manipulation on basketball free throw performance (P = .93).
Intraocular pressure is sensitive to anxiety-induced manipulation during basketball free throw shooting, showing an increase in parallel with accumulated anxiety. Based on these findings, IOP may be considered a promising tool for the assessment of the level of anxiety in certain sport situations. Future studies are required to explore the generalizability of these results in other scenarios with different physical and mental demands.