Welcome to week two of “Vision and your golf swing”. This information is an excerpt from my new book Swing Flaws and Fitness Fixes.
If you missed week one go to my archived articles.
Here we go!
Receiving the appropriate vision evaluation
For visually-guided balance to be most stable the total visual system must be operating at peak efficiency. First and foremost the “Hardware” must be evaluated and any limitations corrected. Without such intervention the “Software” skills, including balance, can never be fully operational.
Relative to the vision “Hardware” I first recommend that the golfer receives a comprehensive VISION exam, not EYE exam, by a knowledgeable vision care practitioner (VCP) who “Sets the Vision Performance Bar” higher, and evaluates far more than just acuity (clarity of sight; 20/20 or 6/6, etc), presence of nearsightedness, farsightedness or astigmatism, and eye health. The VCP should also evaluate, at minimum, such skills as two-eyed use, depth perception at distance, and eye-movement and fixation skills. Visual acuity should be maximized and balanced between the two eyes for maximal depth perception, spatial awareness and balance. Most eyecare practitioners do not apply a different standard to golfers or other athletes versus the average patient. But, the visual and environmental demands are far greater and unique for athletes than non-athletes.
There is a solution
If a vision correction is deemed appropriate I attempt to place every golfer, no matter what age, into single vision soft contact lenses, preferably a daily disposable option. Daily disposable contact lenses provide maximal comfort and clarity for every round. Contact lenses are superior to traditional spectacle corrections from both an environmental and optical standpoints. There are no problems with lens reflections, fogging, sweat, foreign debris, surface scratches, frame/lens weight, frame interference, pressure points or optical distortions with contact lenses. Blurry vision, optical distortions inherent with prescription lenses, and frame interference can have detrimental effects on golf performance, including stability and balance.
Vision / balance relationship exercise #2:
The impact of bifocals on golf performance
For those about 50 years old and now wearing some form of eyewear with a “Bifocal” (or “No Line”) prescription for daily use, such a near vision correction is unnecessary, and possibly performance limiting, in golf. The bifocal generally blurs sight beyond the reading distance, therefore blurring the ball and clubhead. To avoid the blur, the golfer then makes a compensatory change in head orientation to see clearly around the blur zone, resulting in a changed posture, balance and swing mechanics. Such a prescription distorts the periphery resulting in false spatial information, which can lead to instability and balance issues. Our research has shown that the visual demands of golf do NOT require a near prescription during play to see clearly. Normally, the only near demand during a round of golf is the scorecard. In the bright outdoors our pupils are smaller than indoors resulting in greater depth of focus (or field) resulting in the ability to see clearer much closer to oneself, including the scorecard.
Golf, reliant upon visual precision in many angles of gaze, is an endurance sport in that it is played for hours under extremes in environmental conditions, including glare and shadow. Many golfers who wear sunglasses, park their eyewear on the top of their caps, particularly on the green, because the optics, tint, or frame interferes or distorts their vision. A golf-specific pair of sun eyewear is recommended to filter out potentially harmful radiation from the sun, such as UV and blue light, to allow the golfer to be more comfortable, and to provide better clarity of the golfing environment. As discussed previously, prescription eyewear has inherent optical distortions which can effect judgment of critical visual information on the course. But, even non-prescription eyewear includes varying levels of distortion, which can result in inaccurate reads of the green. Nike’s golf specific eyewear incorporates technologies to address the limitations of optics, tint, and frame interference and comfort. (go to www.NikeVision.com for specific product solutions)
Types of lenses
The lens tint must allow one to see safely, comfortably, and accurately. For those of you who currently wear or have considered wearing polarized sun eyewear, this technology can limit golf performance. First, it slightly reduces visual clarity due to its composition. Secondly, it reduces the amount of critical visual information coming off of each blade of grass, which varies with angle of gaze, head orientation, angle relative to the changing angles/directions of the sun, and contour of the green. Polarized lenses were developed for the fishing industry. They reduce the harsh glare off of the water, but unfortunately, when on land, they induce variability, an enemy of the golfer.
What about the darkness or lightness of the tint? While snow reflects ~85% of light, and cement ~45, grass reflects only 3-7%. Therefore, to best capture the critical information reflecting off of each blade of grass for contour recognition, a golf-specific lens tint should be much lighter in shade that a general use sunglass. General use lens tints, which are fairly dark in appearance, transmit only ~13-15% of the light reaching the eyewear. A golf specific tint should reflect more than 20%, in the range of 23-25%. In summary, a golf specific non-polarized tint which transmits only the critical colors of the blades of grass, ball and other surrounds, and is lighter in density than traditional tints, is recommended.
Vision / balance relationship exercise #3:
Think of Polarized lenses as a type of Venetian Blind to filter out reflected glare. While wearing polarized sunglasses, standing near water facing the sun with bright glare reflected, tilt your head back and forth towards each shoulder as if to pour water out of your ear. You will notice the harsh glare alternating between an uncomfortable bright and a more comfortable dim reflection. Next, repeat the demo while standing near the edge of a green with varying contours, and facing towards the sun at a relative low angle,. You will notice variability of the appearance of the grass and perceived topography.
Lastly, head position and angle of gaze can influence depth perception and balance. Looking straight ahead is dramatically different than looking to the right or left while holding the head in a downward direction and lateral position while putting. Exercising these various physical and ocular postures for improved efficiency is recommended.
Vision / balance relationship exercise #4:
While standing on one foot (alternating right or left) tilt head from straight ahead gaze to the putting posture and feel the pulling sensation and decreased stability. Gradually exaggerate the angles of head torsion and angles of visual gaze. Hold such gaze. You will feel even greater pulling sensation and instability.
