Studies show they work best when applied in an area of the cheek or nose that the eye can see

By Mike Maloney

Glare may be caused by dazzling stadium lights or the sun, but and it can also come from light that is reflected off from a smooth shiny surface. The second type of glare is why athletes apply adhesive backed patches or grease paint to their cheeks in the area directly under their eyes.

When an athlete sees something out of the corner of their eye, they are using peripheral vision. Peripheral vision is good when it enables the athlete to avoid an obstacle, like an opposing player, and bad when it causes an unnecessary distraction. The human eye is capable of seeing more than 180^o at all times and the brain is constantly processing all of the information that is received and determining what is important (informational) and what is not important (non-informational).

Most people see part of their nose and their cheek in their peripheral vision at all times and the brain has learned to ignore them as being non-informational. When a splash of light suddenly reflects off from the nose or cheek, however, the brain needs to process that information and determine if it is important or not. Causing the brain to process non-informational input is a distraction that could easily impair an athletes ability to concentrate on tasks like catching or hitting a ball.

Athletes have been using dull finish, dark colored materials like grease paint and shoe polish for many years in order to prevent light from reflecting off from their cheek and into the peripheral areas of the eye. Nowadays, many of them use adhesive backed patches which are easier to apply and remove and less likely to get smeared into the eye.

Our laboratory performed a series of tests to determine how well the performance of eye patches compare to grease paint and we also tested some new over-the-nose patches that have recently come on to the market. Since people have a difficult time quantifying the amount of light that is being detected in the peripheral areas of their eyes, we performed the tests using a specially equipped mannequin. A photo diode was attached to the mannequins right eye and positioned where the rods and cones responsible for peripheral vision are located.

A lamp was positioned so that light reflects off from the mannequins nose and cheek and the amount of light reaching the photo diode in the eye was recorded. Eye black was then applied to the area of the cheek directly under the eye and another reading was recorded.  The test was repeated 5 times and the results showed that the eye black reduced the amount of light entering the peripheral area of the eye by about 1.5%.  That may seem like a small change, but because there is no way to determine how much distraction is too much distraction, the goal should be to reduce or eliminate as much as possible.

When we tested the adhesive backed strips, we found that they reduced the light entering the peripheral area of the eye by about 2.5%. Since the eye black and the adhesive strips were applied in the same location and have about the same color and texture, it appears the advantage for the adhesive strips comes from the difficulty applying uniform amounts of eye black at the same location for each test.

We also tested adhesive backed strips that cover both the cheek and the bridge of the nose and found that they reduced the light entering the peripheral area of the eye by about 12%. The bridge of the nose is a larger reflective surface than the top of the cheek.

Should your players use anti-glare products? Our tests clearly demonstrate that anti-glare products can reduce distractions caused by sudden splashes of light, entering the peripheral areas of the eye, from reflections off from shiny surfaces on the players cheek and nose.  For maximum benefit, the anti-glare material should cover any area of the cheek and nose that the eye can see. When the anti-glare material is first applied, it may actually create a temporary distraction until the brain gets used to seeing it and classifies  it as non-informational. As a result, anti-glare products should be applied well in advance of taking the field for an athletic event.

About the author – Mike Maloney is President of Bjorksten Research Laboratory and has over 40 years of experience testing consumer products and sporting goods. He holds patents in several areas and has published previous articles on testing and the development of testing devices. He developed the test apparatus and the test protocol for ASTM method F 1900 "Standard Test for Water Resistance of Footwear Using a Walking Step Simulator".