Vision and Athletic Performance: Data from Agility Dogs

Abstract

Background: To explore the relationship between vision problems and athletic performance, we measured refractive error and binocular vision in highly trained canine athletes. This group offers the opportunity to examine vision effects pristinely, without any influence of corrective lenses or vision therapy. Such a study is impossible in humans, but can add insight about the influence vision has on athletic performance in general. Methods: 210 dogs were recruited via word of mouth and examined at agility events in California, Texas, and Washington for cover test near and far, prism bar vergence near and far, Hirschberg and Bruckner tests for eye alignment, and retinoscopy. Owners and/or trainers categorized each dog as a good or poor jumper. Results: 190 dogs qualified; 54 (28.4%) had binocular disorders and 136 (71.6%) did not. Among those without binocular problems, mean SE was +0.07 D for good jumpers and -0.82 D for poor jumpers; poor jumpers were significantly more myopic and had more astigmatism than good jumpers. However, because the distribution of refractive errors in our sample was broad (from -3.00 to +3.00 spherical equivalent), some myopic dogs were good jumpers and some emmetropic and hyperopic dogs were poor jumpers. Binocular vision problems had a separate and sometimes additive effect, with anisometropia and unilateral (constant) strabismus more strongly related to poor jumping than alternating strabismus. Regression analysis showed that binocular competence had relatively more weight in jumping than refraction. Conclusions: Refractive error and binocular problems can affect jumping behavior in highly trained canine athletes. However, these vision problems are not predictive for any individual case, and as with human athletes, some individuals appear able to overcome physical attributes that for others are limiting. The results support the importance of vision, and in particular binocular and refractive problems, to athletic performance for humans as well as canines.