Saturday, January 16, 2016 - Viewing the Tennis World as a Map

15 years ago I was living in Austin, TX and was starting to really get involved with league tennis through the Austin Tennis League and USTA. As a player I was given a t-shirt, a schedule of matches, and a list of the match location addresses with driving directions. I loved the tennis and getting to know people and after about two years I formed my own team. As a captain, I had to figure out which tennis centers suited our key players and often had to do last minute venue changes due to spotty rain or court problems. Maybe it's the way my brain works, but even after years of playing all over town, I couldn't visualize where court locations were in relation to one another. So, I set about drawing a map of Austin (using MS Paint) and putting all of the tennis courts on it (See

It was a fun project and I especially enjoyed finding hidden tennis courts and sharing the map with my fellow league players. I printed out copies and even started a Web site ( What was great about the map on the Web was that you could click on a location and see its information. What was not so great was the onerous process of maintaining it. Some people had asked whether I could do the same for their city, and I had to explain how my project really wouldn't scale due to its "hand drawn" nature.

But that changed in 2005 after Hurricane Katrina. I read an article about how some software engineers where I work (National Instruments) used a thing called Google Maps to create a Web-based system to help New Orleans refugees find their families. It was an awesome application of technology for the greater good. You could add your information and point on the Google map, scroll around, zoom in, search by name, etc. I realized I could use the same Google Maps technology to replace my hand drawn map with a feature rich map of the world with tennis courts pinpointed on it. I also confirmed that the satellite images available on Google Maps were good enough to find tennis courts across the globe.

Mapping the United States - let alone the World - was a daunting task to contemplate, however. I had determined from my initial Web site that I wasn't going to get rich doing it - I would need to keep my day job. But, I would always imagine some kid finding a court to play on and getting out there because of the work I was doing. I truly believed that tennis is a life changing sport and I wanted to do things that would help grow the game. And so in 2006, TennisMaps ( was born with the goal of creating a tennis courts map for every city in America.

Ten years later TennisMaps is about 40% of the way there with over 40,000 tennis court locations mapped in the United States. It is available free of charge for use on desktops at and any tablet, phablet, phone or mobile device at TennisMaps also now includes all USTA tournaments on its maps as well as teaching pros affilliated with Why is the job only 40% done in ten years? Well, much has to do with my own stubborness about data quality - wanting to ensure that the process of discovering courts covers every square inch of a region and follows a standard format of data collection. Have I tried more automated ways of finding courts? Yes. Have I given up on better techniques for finding and maintaining court data? No.

One of my core beliefs is that seeing tennis courts, events, and people on a map without a lot of distractions is a better way to get more people playing tennis. Finding the data itself may become easier and easier as we march further into the information age. What will be key is presenting it in a way that encourages discovery of new opportunities to play in your tennis community. I'm going to continue to look for ways to incorporate new technologies for gathering tennis information and making it available through the lens of TennisMaps. Just like playing tennis, I am greatly enjoying the challenge, personal growth, and the people I am meeting along the way.

Sunday, April 7, 2013

Fixing Double Faulting

When I was in my 30's I entered a tournament in Austin Texas called the Hotter Than Heck. It was in June or July and I wasn't playing a lot of tennis - probably a match every 2-3 weeks. I practiced for about a week prior and had a strategy for playing singles. I was going to be a serve and volleyer. My first match went well. I played an inexperienced high school kid and won easily. My second match I played a guy my age and we were in a battle. Eventually, even though he was up 4-2 in the first set, he threw in the towel because it was incredibly hot and he wanted to save his energy for doubles with his dad. I appreciated the chance to advance to the semi-finals. The next day, I got up early for my semi-final match and my arm was pretty sore, but I was ok to play. I started the match and was having trouble hitting my serve in - both first and second. As the first set progressed, my serving control got worse and worse and mentally I felt lost when I threw the ball up into the air. I had no idea where the serve was going - in the net or in the fence. After losing the first set badly, I decided to serve underhand in the second set. It at least allowed me to play some points on my serve. And, at first, it threw my opponent off and I went up 4-2. But eventually, he figured out how to attack my weak underhand serve and I was playing a nervous game in all facets. I lost the set 7-5 and the match.

This was the worst my serve ever was, but I've had serving issues starting in high school. In high school, I would pat my second serve in because I didn't know how to hit a topspin serve. When I first started playing league tennis in my early 20's I was developing a topspin second serve, but I would still have patches where I would double fault at a rate of around 50% - as in half of my service points ended as double faults. It got better with more practice and experience. I eventually got to the point where I would throw my serve into the air and swing hard and expect it to land in. My #1 rule was to always swing hard on every second serve - no matter how much pressure I was under. Rule #2 is to translate all of that effort into as much topspin as possible. After a while of following these rules, I found that more often than not, it would land in.

However, I've had other patches where my serve really left me. Again, it was when I hadn't been playing a whole lot of pressure matches and then suddenly was put under more pressure than normal - like playing a tournament for the first time in 3 years and having been out of league tennis for 2 years. So, I would say one of my first rules for avoiding double fault problems is to hit serves under pressure. If I haven't served under pressure in a long time and suddenly I'm in a pressure situation, I should expect problems. In other words, there is no substitute for match pressure to "toughen" your serve and make it less prone to breaking down . You've got to find a way to hit your serve under pressure and the only way to get better at that is to practice it under pressure.

So, you can play a lot of matches and hit a lot of faults as you gain confidence in your serve. Make sure you are playing a match at least 2-3 times per week. That's the magic number. If you play that much, your consistency will be there in all aspects of your game. Eventually, your mental toughness on your serve will improve. You will develop your own tactics for dealing with pressure. Once you get your serve to where you trust it, if you are playing with that frequency, it will continue to be trustworthy.

But, what can you do to simulate pressure in practice? Here are a couple of ideas
  • Play a set against an imaginary opponent where if you get either your first or second serve in, you win the point, but if you double fault, you lose the game. So, you have to get a serve in play on four consecutive points to win the game. You serve every game. Can you beat this imaginary opponent? Also do this drill simulating having a doubles partner at the net. Serving in singles is definitely different than doubles, so practice both situations.
  • Play a match against a real opponent where you only get one serve - i.e. if you miss your first serve, you lose the point. Again, play singles and doubles matches in this way.

When you've lost confidence that you can hit your serve in, the first thing you should do is start hitting serves into the service box. Stand at the baseline and hit very relaxed serves into the service box. Simplify your service motion - keep your general motion but do everything at about 50% - legs, backswing, toss, speed, etc. The idea is to just allow yourself to hit the ball in the box. Each time you hit a serve in very loudly say the count. When you get to 50, switch to the other side and repeat up to 50. There is no penalty for missing and you can serve at a brisk pace. You're just trying to train your muscles to hit the ball into the box again.

Next, do the same 100-ball drill but focus on two things:
  • A good toss in your comfort zone
  • Watching the ball like a cat
Don't worry about a perfect or overly high toss. Just get it into a spot where you can hit it comfortably. That is usually into the court a little bit and in the line made by your front foot that extends to the net post. If you want to know what watching the ball "like a cat" means, find a video of Andre Agassi's eyes returning serve. Once that ball enters your hitting zone on the serve, don't take your eyes off of it and focus on nothing else. For practice, while you are not hitting the ball overly hard, watch it all the way to the service box. The first time I tried this, I was amazed at how well I could see the ball.

Next, do the same 100-ball drill, but focus on putting topspin on your serve. Keep your motion relaxed and simple. Hit the ball up. Adjust your toss a little more over your head. Focus on brushing up on the ball. But above all else, keep your speed at 50% and everything relaxed. Keep watching the ball like a cat; try to see the ball spinning as it flies up off your racquet and then down into the service box. Can you hit the ball into the box with 100% confidence?

Lastly, add a little more pace to your serves in the 100-ball drill. Keep in mind that you should still be relaxed and that you should only be speeding up the process at the END of your swing. The END of your swing is the only time you should feel that you are moving faster than your previous iteration of the drill. Focus on putting the toss where you want it, putting lots of tospin on the ball, and watching the ball all the way to the box. If you are not happy with how the consistency is, dial things back again. Don't move on until you feel that you are hitting most of your serves in.

Monday, March 25, 2013

Second Serve Topspin

Getting good topspin on your serve is key to having a second serve that you can trust. If you have a "feel" for hitting your serve with topspin, you will trust that you can get it in with enough pace and spin to be effective.

I had to work many years to develop a second serve that I could trust. I used several visualizations to get there. One of the more powerful ones is to imagine my racquet face being horizontal to the ball at the point of contact rather than up and down. Normally, we imagine the racquet standing straight up and down (vertical) as we hit serves and overheads. In the case of hitting a topspin serve, we can imagine the racquet in a horizontal position (like for a groundstroke) that brushes up on the ball, to give it topspin. Below is a video that takes this visual to the extreme and even has some drills to practice the motion.

Tom Avery Topspin Serve

I am careful to call this a visualization. If you watch second serves in slow motion, the racquet is not in a horizontal position when it contacts the ball, but it is close.

With this in mind, watch this video that shows modern players hitting topspin serves:

Lloyd Second Serve Lesson

You can also compare this to Bill Tilden and his pupil back in the days when the American Twist was being invented. I'm especially impressed with his student's racquet motion.

Bill Tilden

To get your racquet in the proper position to where it will snap from a horizontal position that contacts the ball in a way to impart topspin is the key. It will take practice and visualizations. What seems like a big change to you is probably a little change to your swing in reality.

Note that Bill Tilden says that your arm needs to finish out to the right instead of coming across the body to the left.

If you want to examine a topspin serve in slow motion, here are some good videos.

Slow Motion Topspin Serve
Notice where the arm ends for the server in the slow motion video.

A pro who coached Andy Roddick a little when he was young once told me that at 9 he could hit a kick serve that would bounce over your head. Let's look at his second serve in slow motion.

Andy Roddick Topspin Serve

Just like Big Bill says, on an American twist serve the arm ends on the right side of the body. To achieve this will require pronation. Pronating your wrist allows the ball to go toward the target but your arm ends off to the right. After I watched the Nick Bollettieri video below and practiced it, I started hitting big kicking American twist serves!

Nick Bollettieri Pronation Practice

Now that you know what to look for, watch all of these videos again. Then practice. Then watch the videos again. Then practice some more. You get the idea. Here's a checklist for hitting a kick serve.
  • Pronate your wrist (Bollettieri).
  • Brush up on the ball with the racquet more horizontal (Avery).
  • Focus on your arm finishing off to the right. (Tilden)
  • Toss the ball over your head (Avery, Lloyd, Tilden).
  • Arch your back (Roddick).
  • Bend your knees and explode up and into the court (Roddick).
Put the toss in the proper location (above your head instead of out to your right), and then work on your motion to incorporate a fast wrist snap and arm path that brushes up on the ball and finishes to the right. Remember that your wrist snap should pronate horizontally. Then, don't forget about your legs and torso. We want legs pushing us up and into the court for free and easy racquet acceleration. Our torso faces up to the sky initially so we can brush up on the ball over our head.

Monday, March 18, 2013

"Sonic Serve" Revolutionized My Serve

A couple years ago, I found an old VHS tape by Nick Bollettieri called Sonic Serve and watched it. The major difference between my existing service motion and the Sonic Serve was the angle of my shoulders. My existing serve had my shoulders fairly level, and the Sonic Serve calls for the line of the shoulders to be in a 7-o-clock position (close to vertical). It took a couple weeks of really focusing on trying to get my shoulders in that position, but the results were dramatic. I found that my first serve became a lot more consistent because I was snapping down more and keeping it from going long. I also found that I could ditch my old second serve motion which was drastically different from my first serve motion, and use my new first serve motion with more spin (grip and wrist action change) for a second serve.

Below is portion of the full "Sonic Serve" video that goes over the fundamentals. The full video gets overly repetitive:

Drills to Practice Sonic Serve:
  • Throwing Form: Practice the elements of throwing with power including getting a full stretch of the chest and using the left (off) arm to pull to accelerate.
  • Throwing Up: Practice the serve without a racquet by throwing a tennis ball straight up into the air. Stand at the service line and try to throw the ball up so that it will come down on the same side of the net.
  • Set To Launch: You should be able to balance in the set to launch position. Practice the service motion with the racquet and tossing the ball in the air, but freezing in the set to launch position (hip out, knees bent, arm up) and letting the ball drop.

Saturday, January 26, 2013

Lessons From 1991 US Open Edberg v Courier

The video below provides many examples of my core principles for winning points in singles play.

Sunday, September 30, 2012

Really Good Forehand (and General Tennis) Concepts from Florian Meier

Florian Meier has some excellent advice for improving your forehand in this video series:

There are three videos and they are all quite useful. The important take-aways are:
  • Go down (knees bent) and up (knees extend) on your groundstrokes for power.
  • Turn fully (off arm parallel to baseline) on groundstrokes for power.
  • Hit through the ball (extension) for depth on groundstrokes.
  • Slow things down and do shadow swings to teach your body the right movements.
Very concise and sound advice.

Monday, August 20, 2012

If there was a magic 'Play Better' Pill, Would you take it?

Of course you would! Or, you might ask: "What is the catch? Does it give me an irregular heart beat or features of the opposite gender?" That is a good question, and I hope you would at least ask it before swallowing any magic pills.

Let's talk about what a "pill" is. A pill is something you eat which helps you play better tennis. Obviously, you don't want to take a pill that has horrible or life threatening side effects; but would you take a pill to play better if it tasted bad? I bet you would. Would you take a play-better pill if you had to take it at a specific time before your match? Yeah, that's not too difficult. Would you take a pill if you had to experiment with which type and dosage worked best for you? That requires a little work; but if it means you'd win more, you'd do it.

Magic Pill #1: Proper 24-hour Pre-Competition Meals
You can improve your athletic performance if you come into the event with your body in the following state:
  • Fully hydrated
  • Mostly empty stomach
  • Muscles loaded with glycogen (fuel)
Here's a plan you can follow to arrive at the net in that state.

The Day Before Competition
  • Force yourself to drink nothing but water. If you are a caffeine user, you are allowed one caffeinated beverage (12 ounces); caffeine withdrawl starts 12-36 hours after stopping usage and you don't want to enter withdrawl. Other than that, you should drink only water, and in the amount of 48 to 64 ounces (based on your size) throughout the day. Start with a big cup when you first wake up. Drink water with lunch. Drink water with dinner, and not after. You don't want to have your bladder disturb your sleep.
  • Eat meals high in complex carbohydrates and low in fat. Complex carbohydrates get converted to glycogen which is the fuel for your muscles. The more complex carbs you eat, the more glycogen gets packed into your system. Fats leave the stomach slowly and slow down the digestion of other foods. Examples of complex carbohydrate foods are: rice (brown is best), pasta (spinach, whole grain, rice are maybe best), oatmeal and other whole grains products (e.g. whole grain bread), beans, potatoes, peas, vegetables, and fresh fruits. Here are some sample food ideas:
    • Breakfast Ideas: whole grain cereal with skim milk, instant unrefined oatmeal, whole wheat toast with apple butter, whole wheat apple bread or raisin bread, bran muffin, buckwheat pancakes (no syrup!), banana, prunes, raisins.
    • Lunch & Dinner Ideas: baked potato (no butter! can use plain yogurt to top), sweet potato, raw or steamed vegetables, brown rice, pasta (with low fat sauce like marinara), soup (split-pea, bean, or lentil).
The Day Of Competition
  • Six hours prior to competition, eat a high carbohydrate meal. Use the guidelines from the "Day Before" rules. Drink 8 ounces of water with this meal.
  • Two hours prior to competition, eat a small meal that consists of half your weight in carbohydrates. So, if you weigh 150 pounds, eat 75 grams of complex carbohydrates. You can find the amount of grams of carbohydrates on the nutritional info label on your food. For instance, whole wheat pasta has around 20 grams of carbs per ounce. Whole wheat bread has around 15 grams of carbs per ounce. A large baked potato has around 60 grams. Don't eat ANY Fat with this meal. Everything should be plain. Eat one piece of fresh fruit (apples are great). Drink 8 ounces of water with this meal. You should still be hungry.
  • 45 minutes prior to competition, if you are a caffeine user, drink your caffeinated beverage.
  • 15 minutes prior to competition, drink 16 ounces of water.
  • During competition drink 8 ounces of water every 30 minutes - not all at once - but gradually.
  • During competition eat 2-3 ounces of fresh fruit every 30 minutes. Banana, apple, and raisins are great.

Magic Pill #2: Caffeine
Caffeine is a commonly used drug that has physiological and psychological affects. Generally it has positive affects when it is administered and withdrawl symptoms for regular users who stop taking it. Excessive use (see below) is banned by collegiate associations (NCAA, NJCAA, NAIA).
  • Caffeine in excess of 15 micrograms/ml in urine is illegal in NCAA & NJCAA (perhaps NAIA) competition. You have to drink around 8 6oz cups of coffee to reach that level (800 milligrams of caffeine). But be careful, some coffee is stronger (up to 200 milligrams/6 ounces), so, never drink more than 4 cups in a 6 hour period of time.
  • Caffeine reaches peak blood levels at 45-60 minutes and takes up to 6 hours to completely leave the system.
  • Caffeine withdrawl symptoms begin 12-36 hours after the last dose and peak at 20-40 hours. Withdrawl symptoms will generally end after a week. Your mental and physical performance will suffer if you are experiencing caffeine withdrawl.
If you are a habitual caffeine user, you will for sure want to make sure you have caffeine in your system when you are playing. You may be a habitual caffeine user and not even know it because it is found in so many products - soft drinks, chocolate, energy drinks, etc.

Caffeine can have quite different effects on different people. For instance, for me, it greatly improves my mood and mental clarity if I get about 200 mg (1-2 cups of coffee), but makes me overly nervous if I drink 4 cups of coffee. I've also noticed that I don't get the same effects from other sources of caffeine as I do from coffee.

Caffeine can be a magic pill in two ways.
  • Always avoid caffeine withdrawl if you are a regular (3 or more times a week) caffeine user. Give yourself at least a small dose 45 minutes prior to competition.
  • Even if you aren't a regular caffeine user, you may find that a dose from a particular product at a particular amount improves your tennis game. Start with something like a 5-hour energy drink (200 mg) or a cup (6 ounces - approx 120 mg) of coffee 45 minutes before a match. Note how you felt and how well you hit the ball. If you felt a big difference in your balance, you may want to try a smaller dose. If you felt little at all, try increasing the dose, but be VERY careful once you get past 400 mg, and if you are a college player, never go over 700 mg. Keep a notebook of what you took and in what amount and then how you played and felt.
  • Since caffeine causes you to process more water out of your system, make sure you are drinking plenty of water - perhaps an extra 8 ounces for every 200 mg of caffeine.
Scholarly Articles on Caffeine
Dr. Roland R. Griffiths, John's Hopkins, 2011 Publication
Dr. Roland R. Griffiths, John's Hopkins, 2003 Publication

Magic Pill #3: Pineapple
Almost everyone who plays a sport competitively will have to deal with some sort of "itis" like tennis elbow, jumper's knee, and thrower's shoulder. "itis" means inflammation which is usually accompanied by pain which is almost always accompanied by a loss of performance. Usually what is inflamed is a tendon where it attaches to the joint or in its sheath or one of the bursa (sacs of fluid) that cushions a joint. These types of injuries often occur because of overuse of a particular joint or sudden use after months of inactivity. Whenever you feel any pain, the first thing you should do is see a trainer or a doctor. However, among all of the advice you are going to get on how to fix the problem - rest, ice, heat, massage, specific strengthening, bands, anti-inflammatory drugs like naproxen sodium - eating pineapple may never be mentioned and is perhaps your most effective option.

Eating pineapple reduces swelling and promotes healing. It's that simple. Google it and you'll find articles talking about how it has enzyme Bromelain which plays a major role in the body's healing process. I have personally found that it is more effective than taking over the counter anti-inflammatory drugs (NSAIDs) such as Ibuprofen (Advil, Motrin, Nuprin) and Naproxen (Aleve). In one accidental experiment, I found that eating pineapple the night before made it less painful for me to count out numbers with my fingers to my 6-month-old son. It was easy for me to see the difference because I did the same thing every morning and experienced the same discomfort except on the days where I ate pineapple the night before. In another case, I injured my right knee playing basketball. It didn't hurt right away - only two days later, but the pain and swelling got progressively worse and lasted for two weeks. Taking Naproxen Sodium for four days helped but I was still barely able to walk into the third week. The fourth week I was at the NJCAA National Championship and had a hotel breakfast every morning. Each morning I ate about 8 ounces of pineapple chunks. After 3 days, I was walking without major pain and by the end of the week my knee swelling was much better. This was particularly amazing because I was not able rest much that week - a lot of walking at the tournament. When I got home, I got cocky and ran a 5k race with no training. The next day I could barely walk again when I first got up because I had strained my knee and calf muscle. Each morning I experienced the same pain and stiffness until the 6th morning after I ate pineapple the night before.

I would recommend eating 8 to 12 ounces of pineapple the night before any major contest. And heck, why not have some in the morning too. Being pain free and having less swelling and therefore more range of motion is going to help your performance greatly. And, if you are dealing with any sort of "itis", eat pineapple every day. It will help you heal faster.

Appendix A: Reading Labels to Determine Complex Carbohydrates
To determine how many grams of complex carbohydrates you are eating, you can look at the Nutrition Facts of any packaged food. The formula is as follows:
  • Complex Carbs = Total Carbohydrate - Sugars

Appendix B: Foods High in Complex Carbohydrates

Whole Grains
Whole grains are high in fiber, have moderate protein levels, are low in fat and are also a good source of complex carbs. Specific examples include millet, oats, wheat germ, barley, wild rice, brown rice, buckwheat, oat bran, cornmeal and amaranth. Any product that is made from these grains is also complex as well. Whole grain bread, bagels, buns and rolls are examples of these. Also pasta, macaroni and breakfast cereals that are made from whole grains are complex carbohydrates.

Fruits are high in water content, fiber, vitamins and they have virtually no fat at all. Fruits packed with complex carbohydrates include apricots, oranges, plums, pears, grapefruits and prunes.

Vegetables are high in water, low in fat, have multiple vitamins and minerals, and most varieties are complex carbs. Broccoli, cauliflower, spinach, turnip greens, eggplant, potatoes, yams, corn, carrots, onions, all types of lettuce, celery, cucumbers, cabbage, artichokes and asparagus are all examples of these.

Legumes are oftentimes called pulses. These are characterized by seeds that have an exterior pod surrounding them. Beans are a type of legume that is a complex carbohydrate. Specific examples include lentils, kidney beans, black beans, peas, garbanzo beans, soy beans and pinto beans.