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Published on: July 21, 2020
Binocular Function Parameters in Elite Football Players
Jorge Jorge1, Alberto Diaz-Rey1
1Clinical and Experimental Optometry Research Laboratory (CEORLab), Center of Physics (Optometry), School of Sciences, University of Minho, Braga, Portugal.
Background:
To investigate the binocular function in elite football players, and to analyze the differences (i) between athletes who play in different positions and (ii) between players of different ethnicities.
Methods:
We screened 102 professional football players from four teams. The screening consisted of the measurement of refractive error. The binocular function parameters evaluated were: horizontal and vertical ocular alignment for distance (DF) and near fixation (NF), the values of break and recovery for negative and positive fusional vergences at DF and NF, vergence facility at NF, monocular accommodative facility at NF, near point of convergence (NPC) (break and recovery points), and NF stereopsis. All the athletes were men with a mean age of 24.6 ± 4.1 years.
Results:
No statistically significant differences were found based on the athletes' ethnicity, except for ametropia prevalence, negative fusional vergences at DF, and NPC. We verified a statistically significant difference for the value of the break of negative fusional vergence at DF. The values found for Arab athletes are higher by more than 2 prism diopters than athletes of other ethnicities (p = .021). Arab athletes also show NPC values more distant than other athletes (p = .019, and p = .002 for break and recovery, respectively).
Conclusion:
Arab athletes have some binocular function parameters better than the remaining athletes, in particular when compared to Caucasian athletes. When compared to reference studies, athletes' binocular function seems to be better than those of the general population.
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