Science behind TT

Physical Conditioning For Table Tennis

Biomechanics is the study of how the body works together. In the context of table tennis, it is the most opitmal form to hit the ball to generate as much power as possible. Form is widely considered to be the most important thing in almost any sport. Correct form is not a natural movement for most people, and one needs good flexibility, athleticism, and a lot of practice in order to execute correct form. Good form also directly affects power efficiency, as discussed in the previous article. Bad form leads to slow shots, increased risk of injury, and is overall undesirable. In this article, I will discuss the correct method to execute the forehand loop (also called forehand drive, forehand attack) in table tennis. Form is slightly different for everybody. Some people are shorter, some are stronger, and form differs between men and women. However, the general framework of the form remains the same, and the principles also remain the same. One exception though, might be for physical limited people, maybe seniors or people with arthritis. They may not be strong enough. For the purposes of this article, I will assume that you have the physical capabilities of at least an un-athletic person. As it is very difficult to break down the full forehand loop form into words (it would make this already long article longer), I will discuss the general principles and provide some guiding ideas for developing a highly effective form, and leave the rest up to the player.

The main principle for the forehand is that almost all the power comes from your legs and trunk. Very little comes from the arms and shoulder, which is only responsible for holding the paddle and transferring the power, not generating it. This is, in my opinion, the most common mistake players make when executing the forehand loop. Most of their power comes from their arm and shoulder, resulting in greatly decreased power and efficiency. Your legs and torso are much thicker and more powerful than your arm. It can generate massively more power and is a much more stable platform, especially if you are trying to accelerate the ball to high speeds. Even if you do not take away anything else from this article, I hope you grasp this concept. Most of the power is generated from your legs, it is then transferred to your torso, and finally to your arm. Some people might generate more power from the torso, maybe others more from their legs. Very few top level players generate most of their power from their shoulder or arm.

The core also plays a pivotal role in the forehand, and almost every shot in table tennis. The core is like the power line of the body. Incorrect usage and engagement from the core will lead to loss of power. Even if you don't realize it, you probably do tighten your core when you hit the ball. The core stabilizes the entire body, and it makes sure that what needs to stay rigid stays rigid. It also can directly generate power when you twist your torso. Next time you train your forehand, pay attention to your core and how you are using it. Try tightening it more and engaging it. Many players also often have a weak core, which leads to their shots being unstable. This brings up the topic of physical conditioning, which, in my opinion, is extremely important if you want to truly excel at this sport. A weak body cannot generate strong shots. I will discuss physical conditioning in the next article.

Finally, if the arm doesn't generate power, then what does it do? When people first look at the arms of top players, it seems like they are using their arms a lot. That is actually not true. The actual movement that comes purely from the arms is very little. Almost all the movement is from the legs and rotation of the torso, which in turn, moves the arm because it is attached to their body. The role of the arm is to transfer power to the ball. The paddle can be considered a part of your arm. In order for the arm to do its role, it has to be extremely relaxed, only just barely tense enough to maintain form and hold the paddle. If the arm is tense, then it will be rigid, and thus it cannot make the "whipping" motion at the end and generate power. Power will be absorbed by the overly tense arm. At first, the arm should be as relaxed as possible. It should start moving at a very slightly later timing than the torso, since it is not generating power on its own. This difference in timing is very slight however, and you should not deliberately try to make your arm swing later. Finally, right before contact with the ball, the arm can be more tense and accelerate into the ball, contributing just a little more power. It should feel like you're "grabbing" the ball. The shoulder plays a very small role in the forehand. The little bit of the movement that the arm does perform comes from mostly the forearm. The last part of the arm is the wrist. Many people debate about whether the wrist should be incorporated into the forehand or not. Many top players do indeed engage their wrist when executing a forehand loop, but it is a very slight movement. For players who have not yet gotten the hang of the forehand loop, I do not recommend trying to incorporate the wrist, unless it comes very naturally to them. Except for penholders. Penholders can and should utilize their wrists in the forehand.

Nevertheless, there are still exceptions to the principles I discussed in this article. The table tennis legend, Zhang Jike, is a great example. His forehand incorporates a lot of shoulder and arm, and a lot of his power comes from his arm. Despite this, he is still considered one of the greatest players of all time. How? Isn't he breaking the principles? When he first entered the national team, the national team coach wanted him to change his forehand form. However, Zhang Jike's personal coach at that time convinced the national team to allow Zhang Jike to continue training with his original form. Zhang Jike then went on to complete a grand slam. Despite his success, I believe that players should not attempt to replicate his form on the forehand. Zhang Jike is an incredibly, incredibly gifted athlete. Very few people's shoulders can handle this kind of rotation and repeatedly execute forehands at the top level. To do this also requires an extreme amount time spent on injury prevention in the form of lifting, stretching, and other forms of conditioning. Moreover, Zhang's career was painful and littered with injuries, suggesting that even he could not maintain such a form. Most professional players' forehands do not look like Zhang Jike's. Another exception might be certain European players who utilize a lot more shoulder and arm than most professionals. However, I mainly focus on the Chinese philosophy for table tennis, since the Chinese have been the most dominant in this sport for the past decades. These European players, and Zhang Jike included, despite incorporating a lot of shoulder, still use a ton of leg and torso, much more than what I see most amateur players using.

Unfortunately, fixing this habit is difficult since players instinctively want to hit the ball in the most intuitive and direct way, by using their arm. It takes years of practice. Despite understanding much of the principles, even I have not fixed my old habits.

One of the most important concepts in Table Tennis is power efficiency. Power efficiency is how much power actually ends up in the ball compared to how much power is used. The best players have very high power efficiency and can use a small movement and very little effort to generate large amounts of power. Almost all the power they use ends up in the ball. Their shot looks effortless. Meanwhile, lower level players may struggle with power efficiency. They might put 100% power into the ball, and due to bad form, maybe 5% gets absorbed in the shoulder, 5% gets jammed into the arm, and another 20% is only released after contact with the ball is already finished. In this scenario, only 70% of the power used ended up in the ball. Low power efficiency hinders a player's ability to develop. They constantly feel like they have to muscle the ball to get power, and in turn, due to trying to hit the ball hard, they will have much lower consistency. In the worst scenarios, even table tennis players can develop tennis elbow due to constantly muscling the ball. One member from my club took a two year break from the game due to a worsening tennis elbow. So, how do we increase our power efficiency?

The easiest method to increase power efficiency quickly is make solid contact with the ball, combining your power with the power already in the ball. This lets the ball sink into the rubber, thus utilizing the strength of the wooden blade, resulting in a longer dwell time and massively increased power efficiency. The sound from a solid contact is crisp and sweet. You will also know you have made solid contact when you feel the vibration of the blade through your hand. To make a solid contact, one must understand that not all power comes from the player itself. A lot of the power in fact, comes from the ball that hits your paddle, from your opponent's shot. A great way to find this feeling is by serving topspin multiball (Look up "multiball table tennis" if you don't know what that is). In China, coaches have kids constantly serve multiball, even when not training with others. Serving good multiball is not easy. When serving multiball, the power does not come from your right hand. It comes from your left hand that hits the ball against your paddle that you are holding with your right hand. Multiball is not tossing the ball and then smacking it with the paddle in your right hand. I recommend players to serve some multiball when they have time, and really let the feeling of the ball hitting your paddle generating power sink in. However, remember that this is still a supplemental exercise and the best way to get better is still to practice with another player. Listen and feel for that sweet, crisp sound. When you feel like a shot is good, try to replicate it. One huge mistake people often make is they try to make solid contact by adding more power. This is not the way. Even weak shots can be solid. Trying to add more power on purpose only adds more muscle, decreasing power efficiency. Even when you think you've heard a solid contact from muscling the ball, it is not the sweet crisp sound a true solid contact creates. A muscled power shot sounds sharp. The only time players should muscle a ball is killing high balls.

A solid shot is not the only way to achieve higher power efficiency, however. Working on a perfect form and perfecting your biomechanics will also lead to a higher power efficiency, but that is something that takes years, even decades, of training and is likely something you are already working on. Meanwhile, going for a solid shot is something you will be able to hopefully apply in your next training session. The journey to making your shot truly solid is still long and arduous. Gaining higher power efficiency is not easy, but the rewards are well worth it. In the end, practice makes perfect.

To apply many of the things I discussed in this article correctly, I highly recommend watching a few videos of Ma Long's forehand (or backhand) and just listening for the sound of his shot and remembering it, to distinguish the difference between a muscle shot and a solid shot.

Table Tennis and the Magnus Effect

February 7th, 2025

by Jerry Zeng, Joyous TT, NVOT

High level players can spin a table tennis ball 10 times faster than the wheels of your car going 60 mph (look it up!). Table tennis balls can spin at around 150 rotations per second, 9000 rotations per minute.

The basis upon which competitive TT is built is spin. Specifically, the magnus effect. Without spin, competitive TT is basically impossible. It’s surprising how many high level players I’ve met before didn’t know this, but used the principle of the magnus effect in almost all of their matches. Think, when your opponent gives you a hard shot, but you must attack it, what do you do? Add a whole lot of topspin? Why? Well, it usually goes on the table that way, doesn’t it? In Chinese terminology, adding spin is literally called adding “safety” (bao xian) in a direct translation, since it makes the shot so much safer.

The diagram above is of a table tennis ball spinning forward, in a topspin motion. Fluids, such as air, like to stick to the surface of things. The same applies for a table tennis ball. The air likes to stick to it as it goes through the air. However, when the ball begins spinning, the air sticks to the ball, and the ball “pulls” and releases the air above it, increasing the air pressure above and decreasing the air pressure below, causing the ball to dive downwards.

In your game, this would translate to you looping a spinny high arc ball, and then diving down back onto the table. The stronger the spin, the stronger the magnus effect, and the less likely your ball is to go long. The ball won’t go into the net because you have added so much height to the ball, and it already has so much forward momentum. It also applies to every other shot you do. If your topspin shot is fast, spin is the reason why it even goes on the table. If you look at some higher level players, like Xu Xin, they often even loop the ball from way underneath the table, and it looks like there’s an invisible force pressing the ball back down on the table. Of course, gravity plays a role, but without the magnus effect, that ball would be going to the moon. This principle is applied to many other shots as well. Sidespin would make the ball go sideways, and backspin makes the ball float upwards! That’s why when you push too hard, the ball will go up. It is also why high level players prefer serving strong sidespin over strong backspin, since backspin will lead the ball to “float” higher and make the ball sometimes easier to receive (of course there are exceptions and variations). The magnus effect applies in many other sports as well. For example, curveballs in baseball. Next time you play, keep this in mind, and remember the importance of spin!