STATIC VISUAL ACUITY
Static Visual Acuity is the degree of detail that can be seen in an object or the ability of the eyes to resolve various sizes of objects at various distances. It is the basis of good vision and is a guide to other visual skills. All athletes should have 6/6 or 20/20 visual acuity in each eye as measured on the Snellen chart.
DYNAMIC VISUAL ACUITY
Dynamic visual acuity refers to the athlete’s clarity of vision while the athlete is in movement or while the athlete is tracking a moving object. Visual acuity refers to an athlete’s static clarity of vision. It is the most common measurement of visual function. The term 20/20 vision, for example, refers to visual acuity.
Why is dynamic visual acuity important in athletic performance?
As a skill, dynamic visual acuity allows an athlete to quickly send clear and precise information to the brain.
The more clear and precise the details, the more accurate is the information that is sent to the brain, and the faster the brain is able to process that information and generate the correct physical movement.
Dynamic visual acuity is critical to improving reaction speed, for example, in sports where the athlete must react to visual cues.
What should athletes do to improve their dynamic visual acuity skills?
Eye exercises which require the athlete to maintain visual focus on a target while in movement, and to maintain visual focus on a moving target, will help to train dynamic visual acuity skills.
- Side-to-Side Eye Movements: Improve athlete’s ability to maintain focus on targets or visual cues appearing in a horizontal plane from side-to-side
- Top-to-Bottom Eye Movements: Improve athlete’s ability to maintain focus on targets or visual cues appearing in a vertical plane from top-to-bottom
- Near-to-Far Eye Movements: Improve athlete’s ability to maintain focus on targets or visual cues appearing in a three-dimensional plane from near-to-far
Loading Visual System: Improve athlete’s ability to maintain focus on targets or visual cues appearing in all directions while the athlete is in movement.
Eye Movements is the ability of the athlete to accurately use the two eyes together to ﬁxate on a target and to maintain this ﬁxation while the athlete and or the target is in motion or stationary. Eyes have three types of movements:
- Saccades: These are quick movements between two points in space usually at a speed of 400 to 700 degrees per second. They are directed towards stationary targets.
- Smooth Pursuits: These are slow eye movements and allow continuous visualization of moving target. The usual reaction time between target movement and the initiation of smooth pursuits is 125-135 ms and the speed is about 30-70 degrees per second. They are used to track moving targets.
- Vergences: These are inward and outward movements of the two eyes together. Eyes can have convergence or divergence movements.
Depth Perception is the ability to judge the relative distances of objects by means of binocular vision.
Peripheral Vision is the ability to maintain an awareness of what is happening outside the direct line of vision. The binocular ﬁeld extends to about 200 degrees horizontally and 130 degrees vertically.Peripheral vision is used to detect movement and shapes while central vision is used for visual clarity and to detect color.
Why is peripheral vision important in athletic performance?
Peripheral vision, because it is the body’s first way of sending messages of movement to the brain, is essential to improving anticipation and reaction speed.Peripheral vision is also critical for self-preservation and protection against injury in contact sports.
What can athletes do to improve their peripheral vision?
It is not possible to expand your peripheral vision beyond 180 degrees. Fortunately, however, it is peripheral awareness rather than peripheral vision that is most useful to athletic performance.
EYE HAND COORDINATION
Eye-hand and body coordination involves the integration of the eyes with the hands/body. It determines the effectiveness of a perceptual motor response to a visual stimulus.
Eye-hand coordination is the athlete’s ability to synchronize finger, hand and arm movements with constantly changing visual information from a dynamic sporting environment.
Why is eye-hand coordination important in athletic performance?
Visual coordination affects timing, reaction speed, body control and balance.
Numerous studies across various sports have shown that eye-hand coordination speed is faster among athletes when compared to non-athletes. In addition, studies have shown it to be a characteristic which distinguishes expertise levels among athletes.
How can athletes improve their eye-hand coordination skills?
Athletes can improve their eye-hand coordination skills with deliberate vision training exercises that require the synchronization of motor movements with visual input.
Effective exercises may vary from simple visual-response tasks that require minimal brain processing, such online computerized reaction speed tests, to more complex visual-response tasks that require greater analysis of visual information, such as juggling, soft toss, or computerized target shooting games.
Visualization is literally seeing an image or movie in your mind. While the word “visual” implies that visualization is a visual skill, it is not. The clarity and quality of the image or movie played in your mind, for example, has little to do with visual skills.Rather, the ability to visualize requires athletes to draw on short-term and long-term memory. For purposes of sports vision, visualization is a brain skill and a sports psychology skill.Nonetheless, vision programs often include visualization training among the skills developed. As such, we have included this visualization section in our visual skills pillar.
Why is visualization important in athletic performance?
The brain does not distinguish between visualization and a real practice, competition or event. In fact, scientific studies show that, in certain cases, mental imagery training can be at least as effective as physical training.By creating an image in your mind and visualizing it over and over again, your brain will start to believe that the event has actually occurred. The more vividly you visualize an event, the realer it will seem, and the most effective you will be at re-programming your brain.
What can athletes do to improve their visualization skills?
Effective visualization does not take a lot of time — five minutes per day is enough.It does, however, require commitment and dedication. Only the truly dedicated athletes, who do their visualization exercises day in and day out, will improve their visualization skills.
Contrast sensitivity refers to the ability to quickly and clearly identify objects in varying lighting conditions and against backgrounds of varying color.
Why is contrast sensitivity important in athletic performance?
Deficiency in contrast sensitivity can interfere with athletic performance by reducing visual information. Errors due to an athlete’s low contrast sensitivity function may be the result of:i) Untrained visual skillsii) Glare from the sun or stadium lights.The higher an athlete’s contrast sensitivity function, the better they are able to process information about objects under different lighting conditions..
What do athletes need to know about contrast sensitivity?
Although most steps taken to improve contrast sensitivity involve the use of glasses or contact lenses, scientific studies show that contrast sensitivity is a visual skill that can be improved through training.
What should athletes do about improving their contrast sensitivity skills?
In light of the above, athletes can improve their contrast sensitivity skills:i) With sport-specific vision training drills aimed at object-background contrast and high-speed object identification.ii) By informing themselves of contrast sensitivity issues particular to their sport; for example, balls lost in the lights or ruts on a slalom ski run.
Visual accommodation refers to the process by which the eye adjusts in order to produce a clear focus on changing distances. Also referred to as focus flexibility, it is the ability of the eye to maintain focus as vision adjusts between near and far targets.
Why is accommodation important in athletic performance?
A degree of focus affects the quality of visual information given to the brain and, in turn, the speed with which such information is processed by the brain.
Any deficiency in an athlete’s ability to maintain a clear focus on moving targets may affect reaction speed, timing, and visual coordination.
What should athletes do about their accommodation skills?
Athletes can improve their accommodation skills by strengthening and conditioning their eye muscles with simple vision exercises, such as pencil push-ups, and exercises with near-far charts and plus/minus lens flippers.
This is the ability to distinguish different colors clearly and accurately in different background conditions.