The old adage “You fight like you train and train how you fight” is the golden rule for combat effectiveness. Science has its own version of this, the SAID principle – an acronym that stands for Specific Adaptation to Imposed Demands. In other words, your body ALWAYS gets better at EXACTLY what it does (and how you do it).

In this series of articles, we are going to look at developing better marksmanship by training your nervous system and specifically your vision.

For tactical & military athletes, binocular vision or using both eyes together to see is paramount for both situational awareness, and accurately identifying and seeing targets. The US Army states in published research that the Sympathetic Nervous System, when activated by high-stress combat situations will force both eyes open. If you have proper functioning binocular vision and you “train like you fight” this should not pose a problem, however, it is estimated that as much as 56% of the general population has a defect in binocular vision. This means that one eye works significantly better than the other and the eyes do not work well enough together for the brain to combine both video streams into one.

For a tactical athlete who can’t produce stereo vision (vision using both eyes) their shooting accuracy may be be reduced with both eyes open compared to using only one eye to aim. To better understand what may prevent you from having good binocular vision, let’s start by defining what vision is and from there, we’ll define the core visual skills every tactical athlete needs to own.

Vision is Different from Eyesight

100% of vision occurs in the brain whereas eyesight pertains to the hardware (eyes). Because vision occurs in the brain, we can use neurological training to make our vision work better. Most people think of “eyesight” when they hear the word “vision”:

Eyesight is simply the ability to see something clearly, the so-called 20/20 eyesight (as measured in a standard eye examination with a Snellen chart). Vision goes beyond eyesight and can best be defined as the understanding of what is seen. Vision involves the ability to take incoming visual information, process that information and obtain meaning from it.”

– Dr. Donald Getz, OD

To help define what vision is, here is a list of Visual Skills as defined by Z-Health Performance Solutions: