In sports, reaction is the initiation of a physical movement in response to some stimulus — swinging at a sinking curve ball, eluding a tackle and making a catch, letting a ball bounce ever so close to the outside of a line. In these examples, an athlete's ability to react can cost him, her, or the team a championship.
Many athletes assume that they have good vision, since they have 20/20 eyesight. But this does not necessarily correlate with the critical factor of sports vision.
_20/20 is a static measure of sight. Sports, on the other hand, are dynamic in nature, and sports vision is the dynamic use of sight. Imagine a wide receiver running out for a pattern. He needs to see the defensive player look back, see the quarterback, and track the ball moving through the air towards him all at the same time. Sports vision takes all this into account. Using the previous example, it involves depth perception (the ability to see things near and far accurately), convergence (the ability for the eyes to cross and focus), divergence (the ability of the eye to uncross and focus), and saccadic eye movement (the quick jumping of the eyes from one object to the next). This is a very complex process that needs to work perfectly for a high level of sport performance. Sadly, many athletes believe that you're either born with it or you're not. The truth is that there are ways to exercise sports vision in combination with physical training