Dr. Gary Polan, O.D. (DrGaryPolan.com) has been the local “go to” Developmental Optometrist for TennisDr students for many years. Whether you struggle with reading or seeing a 130 mph serve, ALL visual skills can be improved! Dr. Polan was one of Dr. Robert Klepper’s “Weekend Warrior” programs on ESPN Radio 710AM a few years ago. Dr. Polan spoke about growing up with Dodger Baseball, seeing a fastball, helping our reading skills, and Sports Vision Training. Did you know that about 5% of all Americans have severe reading disabilities that can be cured? How about that we spend over 10 hours a day looking at a screen which makes our eye muscles less fit?
Tennis, like most sports, is played from the ground up. Transmitting force, gracefully, and in balance is the key to accurate shot making results. In mechanical terms, “gracefully” means without discontinuities or what a coach would call “hitches” in the motion. Minimizing the motion’s unnecessary stops/starts is the major factor to its efficiency.
Balance gives the billions of eye/hand calculations the best chance of accuracy. That is why if an athlete is off balance, their performance must take on more conservative/defensive choices in shot selection.
The more often the player is connected solidly to the ground during ball contact, the more often that player can dictate play and remain on offense. Lack of balance usually, but not always, means the player is on defense.
Interestingly in this sport, hand skills, dexterity, and experience responding to the opponents position, can make up for a deficit in strength, mobility, and foot speed. Age can often triumph over youth for this reason. On and off the court, knowledge is power!
Tennis stadiums around the world have built roofs to protect their tournaments from rain. That said, no roof was as ambitious as the above roof at the US Open!
It’s not often that doubles is featured in pro tennis. Fed Cup and BJK Cup are the exceptions. Serving/Receiving signals, enhanced “I” formation, and first strike tennis are only the take home lessons. The intangibles, the home crowd and the enthusiasm of the worlds singles stars who have to show their doubles prowess, are the real draw for the tennis fan. The revised formats for both events bring the excitement around the world and often in smaller cities where the events are more accessible.
Physical prowess, agility, coordination, and strength have always been the main criteria in judging athletic ability. Most, if not all athletic training programs, have been designed with those criteria in mind, even though our body will only respond to what it can see. Despite this fact, little attention has been paid to vision, which is now the last frontier for those interested in improving their performance on and off the playing field.
This “last frontier” of sports, referred to as Sports Vision (SV), Developmental Optometry, Sports Vision Training (SVT), Vision Training (VT), or Orthoptics, starts with a special eye examination which includes Dynamic Visual Acuity measurements. Regular, “static” eye-exams and the use of corrective lenses are no substitute.
Some of the above name are based on what the training is targeted to do. A child who is improving the ability to track from line to line while reading is practicing Vision Training (VT). A person recovering from eye surgery, trauma, or an acute visual challenge might call this training Orthoptics. This note will focus on an athlete’s SVT.
By undertaking a simple visual training program, ANY athlete can improve performance. That’s because the eye, like the muscles in our bodies, can be strengthened to perform better with exercise. The principle to remember is that no vision skills are passed from our parents. That ALL visual skills are learned!
Q) Who is most known for the best eyes in tennis?
A) Andre Agassi
1) Sport Psychology: The Zen of the Business Like Approach
2) Sport Psychology: The Schedule for Emotions
3) Racket Sports Biomechanics: Brain Function, Eye Skils, and Table Tennis
4) Choosing a Table Tennis Racket From Beginner to Tournament Player
5) Exercise For Your Heart: Determine Your Target Heart Rate (THR) Without Electronic Gadgets
6) Back Pain Relief: A Revolution in Chiropractic Care
7) Sport Psychology: Calming Ping Pong Emotions
8) Can Table Tennis Skills Be Transferred to Other Racket Sports?
9) Tips for Eating Healthy at a Food Chain
A list with links to other publications can be found at: USPTAPro.com
Part 1
(appeared in 2014 Sept/Oct edition of TennisIndustry magazine)
For over 50 years, most tennis courts around the world have been lit with Metal Halide (MH) fixtures, yet few who use them understand their unique qualities. They SEEM to last endlessly, but that’s far from the truth. More importantly, the long reign of MH may be coming to an end in favor of new, much more efficient, “green” technology.
For those new to the lighting industry, a little “Flood Lighting 101” is in order. Metal Halide technology is one member of a family of High Intensity Discharge (HID) lighting systems, which includes street and shopping center lighting.
In HID lighting, electricity heats a metal for several minutes until it vaporizes inside a bulb to give off light, and plenty of heat, which is energy lost. In this case around 8,000 degrees Fahrenheit, which is a lot of lost energy! The next
standard for tennis/sports lighting, will prevent this waste.
As you know, MH bulbs are housed inside a fixture, or “Can”, which has reflectors that focus the light from the back and sides of the bulb downward and outward. It is important to know that MOST current MH light is reflected light from the back and sides of the bulb and not direct light. This makes a difference in its actual and perceived intensity compared to the direct LED lighting you see in office and home lamps.
For a shopping center or highway, the HID metal to be heated is sodium, which comes in two types, Low Pressure Sodium (LPS) or High Pressure Sodium (HPS). Each gives off a “champagne”, yellowish color. LPS and HPS are great for black and white security cameras but not very pleasant for the human eye as it washes out color. This makes people a bit uncomfortable and they do not want to loiter too long in this light. On the other hand, LPS/HPS is VERY efficient, very cheap, and long lasting so it is great for parking lots, alleys, and highways.
For sports, the metal of choice inside the bulb is mercury. Older players might remember the name “Mercury Vapor”. Since mercury gave off a “blue-ish” light, trace amounts of other metals (or halides) were added to help stimulate our eye’s sense of color, so “Metal Halide” was born. MH is also MUCH better for a television camera so prime time sports went “cha-ching”!
The MH Downside
First, experts tell us that MH bulbs lose about 5-10% of their illumination PER YEAR! This is according to Ricc Bieber (Bieber Lighting Consultants) and Greg Moreland (Moreland Lighting LLC). Most lamps we know are either fully on performing near maximum, off, or burned out. But MH is different in that it degrades quickly then levels off for years. Also, most lamps familiar to the public do not require warm up. That 6,000 degrees takes a while!
Why do the experts say ”5-10%”? It’s because a hot MH bulb attracts dust and particulates like the warm computer at your desk
and some environments have more particulates in the air than others. Either way, it’s a significant drop in performance.
(Above) The lighting tech approaches a very cloudy lens. Then he secures a clean bulb and lens. Notice the reflections.
A recent experiment conducted by the author, Bieber Lighting Consultants, and Moreland Lighting LLC confirms this and more. We compared the illumination of old 1000 Watt MH bulbs behind dirty lenses, clean lenses, and new 1000 Watt MH bulbs, all with two types of light meters.
Our results showed that just cleaning the lenses can result in up to 24% more light, and replacing the old bulbs created up to another 40% more light to the court. Plus, it’s smart to do both at once. My vendor charges $105 for the trip, $95 per lamp (for six or more per court), which includes labor.
At that time, all capacitors should be checked and changed if needed and noisy transformers replaced. For an 8 light court, I plan to budget $900 to clean the lenses and replace the bulbs from my vendor. More details on this in Part 2.
Now you know that MH performance drops quickly each year. It flat lines at what lighting experts call “Mean Lumens” which, is around 40% of new bulb capacity. This is despite the fact that it often still ignites and might “appear” to work for many years after that. Here are our MH lighting tips to facility operators and tennis directors:
1) Clean lenses and properly operating MH bulbs SHOULD be uncomfortable to look at directly.
2) Bulbs and lenses can be cleaned but NEVER the reflectors.
3) Budget for MH bulb replacement and lens cleaning at the same time, between 3 to 5 years max.
What’s Next?
In Part 2, we will review the hard costs of running MH lights and compare them to their most likely successor. For now, picture MH lighting like 8 hair dryers on full blast at their 1000 Watt setting, with diminishing performance every year, and significant repair costs. There must be something better than that, right?
What if the next technology could save 70% or more of that power and produce better light? What if it was guaranteed to go maintenance free for 7 years? What if it used American raw materials, created American manufacturing jobs, and could have custom designs for your facility? I would give that a big, patriotic, and green “WOW”! Investment anyone?
Here’s a peak at a possible custom design:
Like the racket design? Me too! More peaks in Part 2.
Part 2
In Part I, we outlined some of the downsides to current Metal Halide (MH) lighting, but don’t get me wrong. MH has served us well for a VERY long time. Now its time for the details, why we need a change, and what the next technology has to offer. Let’s start with the hard costs of MH.
MH Maintenance Costs
What does MH cost per court and what can be saved? Well, we have to make some assumptions, but this analysis will give you an “apples to apples” point of comparison between an MH court and its most likely successor, LED technology. A typical tennis court has 8 MH fixtures (called “Cans”) of 1,000 Watt bulbs or 8000 Watts total. Assumptions: a busy outdoor facility might run them an average of 4 hours a night (an indoor club obviously MUCH more) and 180 nights a year (some climates more, some less). In my city an hour of electricity (a Kilowatt Hour or KWH) costs about 15 cents, times 8 fixtures or $1.20 per hour to light one court. Multiply by 4 hours and you get $4.80 for the night, times 180 nights a year is $864 in electricity costs to light one court. For 7 years, electricity costs $6048. I’ll tell you why we need to use 7 years of power costs below.
My local lighting maintenance vendor charges $105 for the trip, and $95 per lamp or $865 for an 8 lamp court, not including needed transformers, capacitors, and tax, so lets round up to
$900 per court. Individual bulbs may burn out sooner, but this is a reasonable average vendor cost for a budget to maintain appropriate light levels described in Part 1. On an 8-fixture court, over a 7-year period (tell you why “7 years” soon!), you should replace all 8 bulbs twice near the beginning and end of this period, or $1,800. So we have $1,800 in maintenance plus $6048 of electricity over 7 years gives a total operating cost of $7,848.
What Can We Expect Next? Instead of a bulb that loses enormous amounts of energy to heat and sends light in all directions, the likely successor to MH is based on a Light-emitting Diode or LED. You know them from the electronic screens in your TV, phone, and computer. So, why hasn’t LED technology jumped into sports as quickly?
First, even the major lighting companies like Phillips and Sylvania have struggled trying to push enough electricity into the light emitter for sports. But unlike the heat in your computer, the heat for a sports light must be dissipated passively without a fan. Right? It’s been a tricky problem but there are also obvious and HUGE incentives to get it right. Direct light is much more efficient because over 50% of MH light is reflected and tends to spill where it is not wanted. LED light can be easily directed to where it’s needed most on the playing field. In these new sports lamps, the light emitter is encased in 3 inches of shatterproof, solid glass without an air gap. The manufacturer calls it “Explosion Proof” and it might be bullet proof too. Since there is no air at the LED, there is no air pollution, dust, or condensation to block its light over time like MH.
In the pictures below, you can see the clear glass lens and the spokes that passively draw heat away. The core design you see here is EXTREMELY sturdy.
Clearly, and thankfully, the days of the old square “Can” can now be history. LED technology lends itself to an open architecture of customized mounting design choices (see a couple in Part 1). Here are a few more:
This customization also favors native, medium sized companies that are able to quickly adapt to end user needs. These companies would use American raw materials, American employees, and new American factories serving a very large new market. That’s why we say, “Investments anyone?”
Unlike an MH “can”, an LED lamp stays room temperature saving on air-conditioning for indoor use. It won’t break or explode, won’t attract dust or condensation, is instant on/off, does not degrade in performance, can be placed on a motion sensor or a dimmer for mood lighting a party, and can even be remotely controlled from a smart phone. That deserve a high tech “Wow”!
Despite these creative designs, the best innovation is the savings. LED technology is an impressive, environmental alternative to MH power consumption because there is very little wasted electricity. We will know soon if the electricity/maintenance costs will be merely enormous, or spectacular. As of now, it is not known if one or two LED fixtures will be equivalent to one MH 1000 Watt fixture. One complication is that the two light sources cannot be compared with a standard light meter. Yikes!
Operating Costs/Savings
To give you MORE than 1000 Watts of equivalent light with better distribution, you would need to change each can and pole arm to a fixture for your court that holds one OR two LED fixtures. Let’s assume two for now. Two of the LED fixtures pictured above use ONLY 300 Watts! Even if two are needed, 16 LED’s per court (2,400 Watts vs 8,000 Watts) is an enormous 70% savings or $5494 in JUST electricity over 7 years. That deserves a high tech, very green, WOW! Plus, there’s more.
The service costs are also impressive. Because the LED emitter is encased in shatter proof solid glass, mounted to a heavy gauge aluminum base, the parts/bulbs are unconditionally, 100% guaranteed for 5 years but the expected life is 10 years for the LED chip and the housing is guaranteed for 20 years. ===> That’s why the manufacturer advises a conservative, budgeting choice of 7 years maintenance free. They will very likely go longer.
So, we have another $1,800 saved in maintenance, plus $5494 in electricity, for a total of $7,294 over 7 years. Pretty impressive for one court huh? Again, unlike an MH bulb, this lamp stays room temperature so it doesn’t push air conditioning, does not attract dust or condensation, is instant on/off, does not degrade in performance YEARLY over time like MH, can be placed on a motion sensor, and can even be remotely controlled from a smart phone. That deserves another WOW!
Installation Costs
These LED fixtures are designed so that any licensed electrician can do the job. To remove the 8 old arms/cans and install the new LEDs on 8 poles, in parts and labor, is around $15K, so over 7 years about 50% of those costs are returned, at CURRENT electric rates. Most general contractors will agree that‘s pretty impressive for any construction upgrade.
Will electricity costs stay the same? What if just one LED fixture can replace a typical MH lamp? What about LED’s for football, baseball, and basketball? Here’s another option we would like to see get the “green” light:Yes, it’s possible sports lighting of the future might be powered by the sun! The mind truly boggles at the prospects for LED’s in sports and new American workers to get the job done.
Part 1
One day all elite athletes will have their Dynamic Visual Acuity checked and improved. Until that day, all I can do is present evidence of how important it is and how limited the human eye is in the hyper fast, hyper difficult world of tennis.
Part 1 is an astute investigation of the science and practice of professional line calling. An article that helps describe how difficult a task tennis presents for the human eye. Incredibly, this is just for the poor linesmen who are sitting still trying to focus on one bounce of the ball in one spot. Linesman are actually told to NOT watch the ball! Wow!
In stark contrast to this trained professional linesman, most line calls in our sport are made by players who are running, out of optimal position, and probably feeling obligated to their doubles partner. No wonder the demands can get out of control and cause friction among friends!
Part 2 is an article to help put the Part 1 description into practical application for your tennis. The pros now have the benefit of Hawk Eye technology, the rest of us do not. Hopefully, these articles will help you find the proper perspective on your next line call.
~Best of luck with your tennis!
Jonathan
———–
THE INS AND OUTS OF BORDERLINE TENNIS CALLS
By Alan Schwarz
Published: June 23, 2009, NewYorkTimes.com
When a line judge at Wimbledon rules on a hair-splittingly close call and says the ball is out, the inevitably disgruntled player should not only consider challenging the call for review by digital replay system. He should consult a recent issue of Current Biology.
A vast majority of near-the-line shots called incorrectly by Wimbledon line judges have come on balls ruled out that were actually in, according to a study published in October by researchers at the University of California-Davis. To the vision scientist, the finding added to the growing knowledge of how the human eye and brain misperceive high-speed objects. To the tennis player, it strongly suggests which calls are worth challenging and which are best left alone.
The researchers identified 83 missed calls during the 2007 Wimbledon tournament. (Some were challenged by players and overruled, and others were later identified as unquestionably wrong through frame-by-frame video.) Seventy of those 83 calls, or 84 percent, were on balls ruled out — essentially, shots that line judges believed had traveled farther than they actually did.
Called perceptual mislocalization by vision scientists, this subconscious bias is known less formally to Wimbledon fans as “You cannot be serious!” — John McEnroe’s infamous dissent when, yes, a 1981 shot was ruled out. Now that players can resort to a more evolved appeal procedure, the researchers’ discovery suggests that players should generally use their limited number of challenges on questionable out calls rather those that are called in, because such out calls have a far better chance of being discovered as mistaken on review, then overturned.
“What we’re really interested in is how visual information is processed, and how it can be used to a player’s advantage,” said David Whitney, an associate professor at U.C.-Davis’s Center for Mind and Brain and the paper’s lead author. “There is a delay of roughly 80 to 150 milliseconds from the first moment of perception to our processing it, and that’s a long time. That’s one reason why it’s so hard to catch a fly — the fly’s ability to dance around is faster than our ability to determine where it is.”
This is the third Wimbledon in which players can challenge questionable calls for review by the Hawk-Eye system, which uses high-speed video cameras to record balls’ flight. (About 25 percent of all challenges result in overturned calls.) There is no cost to the player when a call is proved correct, but after three such episodes in a set a player may not challenge again. Whether through strategy or residual tennis etiquette, most players leave many challenges unused.
Theoretically, line judges should be equally prone to call an out ball in as they are an in ball out. But when objects travel faster than humans’ eyes and brains can precisely track them — for example, Andy Roddick’s 150-mile-per-hour serves — they are left having to fill in the gaps in their perception. In doing so they tend to overshoot the object’s actual location and think it traveled slightly farther than it truly did.
Both successful challenge calls as well as the overlooked mistakes that the researchers later identified were several times more likely to come on “long” calls than “in” calls. (The same pattern existed at Wimbledon last year, Whitney said, although the paper did not present that data.) So players are better off using as many challenges as possible on balls called out, because those are the calls most likely to be wrong; if a player thinks an “in” call was wrong, chances are his own eyes were as fooled as line judges’ sometimes are.
Without knowing it, tennis officials are already told to try to compensate for this mislocalization effect. Published instructions for United States Tennis Association line judges tell them to “focus your eyes on the portion of the line where the ball will land,” rather than attempt to track the ball in flight. “Get to the spot well before the ball arrives,” they are advised.
Rich Kaufman, the association’s director of officials and a linesman and chair umpire from 1976 to 1997, said that of all things “one of the hardest things to teach new linesmen is to take their eye off the ball.”
“I once asked an eye doctor, then what am I seeing on a bounce?” Kaufman said. “The doctor said that’s your brain working — you think you see the initial point of impact but it’s the blur of the entry and exit of the ball.”
A player using his knowledge of this effect in challenging calls could see a benefit of about one or two overturned points per match, Whitney said, plus any psychological boost from feeling vindicated rather than robbed. But Whitney added that understanding how the brain misperceives visual stimuli can help in more real-life matters, like the design and placement of high-speed safety equipment, automobile brake lights and warning signs of all types.
As for Wimbledon, it appears as if the new information can only help players, not the judges who vex them. Kaufman said: “You have to call what you see. Or what you think you see.”
Part 2
HANDLING LINE CALLS FOR RECREATIONAL PLAYERS
by Jonathan Bailin, Ph.D.
Over the years, I have addressed this issue verbally with recreational players from time to time. It is
so important to them however, that it should be placed here for future reference….
Strong, successful personalities often treat recreational tennis as just another litmus test of
their personal success. That their competitive nature in business should be reflected in all arenas
of their lives. Why not tennis?
Because by definition, it is “recreation”. An important word to keep in mind on court.
I hope you have had a chance to look at the above article on eye skills and line
calling I reproduced from the NY Times. VERY RARELY are bad line
calls on purpose in amateur tournament tennis, and practically never in social tennis.
That said, they are an ever present artifact of imperfect eye sight for all players and officials.
It’s clear that some players become hypersensitive to line calls in general, but a more “recreational”
and relaxed approach to this situation is in order. Here is an adult, big picture approach:
No one wants our favorite sport to have any adverse effect on our friendships. Recreational
players are important cogs in each others social wheel. Your goal should be to have many years
of amicable social and competitive tennis ahead, with all players available, at your skill level.
====> To that end, I propose you use a new line call policy on court– If an opponent even looks at you
funny after you make a call, give the point away! <======
This can be confusing and difficult at first, but it is an important response for all tennis players.
First, admit to yourself that if you are not making a living on tour, no matter what “competition”
you are engaged in, you are playing “social tennis”. That is you are in a very small, tightly knit
community which communicates frequently about ALL aspects tennis. More important than any
trophy or team success, your reputation as a mature person, who others enjoy playing with, is at stake.
Social tennis should test skills, not reputations, because tennis should not be at that
level of importance in our lives. Your business, your family, your contributions to the people
around you, the planet, and your health are that important. Not tennis!
In my professional opinion, suggesting to “Replay the point” is not a strong enough gesture of capitulation to
an opponent who has just taken a risk by questioning a call verbally or by body language. Keep
in mind that they already feel awkward. Your choice is to help them relax by showing an expert
understanding of the situation or heighten their fears that they will face ridicule or rejection.
ALL PLAYERS SHOULD RESPOND TO THAT SITUATION BY– asking for their help in making the call “if you saw it more clearly than I did” and graciously, with genuine intent, offer them the point. Let THEM offer to play the point over and do not offer that option yourself. If you are going to capitulate graciously, go the whole way!
This does several things. One, it demonstrates that you understand the challenges for the human eye. Two,
you are mature enough to have your priorities straight in terms of life and the future fun to be had with these same friends, in the next point, and in the next match. Three, that the continuity and spirit of the contest is more important
to you than any particular point. Even match point!
The pros know that one point matters as often as…. ummm…. Halley’s Comet! In that case, the line judge’s
job is to take the grief anyway. For recreational players, one point matters even less often.
Relax and enjoy your friends!
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