Rowden Fullen (2004)


IntroductionTrajectory of the BallAbsolute Line of SightSmash against LobFlicking the Short BallCounter-hittingService — Speed and TimeSpeed and also SpinRacket CoveringsFriction and also BounceBounce on the TableSpeed, Distance and also TimeEconomy of Movement, Key to SpeedThe Radius of the Stroke and Angular VelocityThe Geomeattempt of the Game


Nothing that happens on a table tennis table is inexplicable as lengthy as you are aware of the standard laws of physics. Once the ball has left the racket, the trajectory and direction is identified by the power and spin fed into the stroke. The trajectory itself is established by gravity, the air resistance and the influence of the spin. A equivalent stroke will certainly constantly produce a similar cause terms of spin, rate and also direction. One deserve to of course suggest out that things will not be precisely the very same relying on wbelow one finds oneself on the earth’s surchallenge. The weight of the round deserve to differ by as a lot as 0.5% depending on whether you play in a place near the poles or in a locality on the equator. However this is really rather meaningless as soon as you think about that the rules enable a variation of up to 5% in the weight and diameter of the ball and at the many 8% as soon as we are talking around bounce.

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Far even more significant variations happen in air press as soon as we talk around elevation above sea level for instance. At 1000 metres air push sinks by 12% and also at 3000 metres by as much as 30%! This has a major influence on both the air resistance and also the impact of the spin on the round in flight. A major championship event played for example in Mexico City will cause the round ‘flying’ in an unexplained manner and also the players should be ready for this, as the trajectory of the ball will not condevelop to supposed criteria. When players talk about a ‘hall’ being sluggish or fast this is a subjective endure. This deserve to depfinish on different floor coverings, lighting, acoustics, warmth and also cold or just the size of the room. It doesn’t mean that the ball is moving in an unexplained manner.

Questions relating to materials and the differing spins and also results can be fairly more complicated as the production service providers have actually not tried to create standardised tests to meacertain exactly what their assets deserve to do. Often proficient players or testers (or in some cases not so experienced) categoincrease rubbers in regards to spin, rate and also control, however obviously these classifications are pudepend subjective. Different players will certainly for example use rubbers in differing methods and one player will certainly regularly be qualified of acquiring far even more out of a particular rubber than one more player would certainly. Such ‘subjective’ trial and error can offer some advantageous information but helps little bit in giving any base for objective measurement once comparing assets from different manufacturers. Also materials and indeed methods and also tactics are constantly in readjust - it is necessary that we constantly have actually an open mind and are all set to look at brand-new concepts and also means of doing points.


After leaving the racket regardmuch less of the spin, rate or direction, the ball is influenced ssuggest by 3 components - gravity, air resistance and spin (Magnus effect)(See diagrams A and B). In the case of topspin, gravity and also the affect of the spin job-related together offering a much more arced trajectory (See Diagram C). With backspin gravity and also the spin determinants occupational versus each various other so that the round will certainly rise initially in a curve before dropping sharply when gravity predominates over the lessening spin (Diagram D). Gravity is constantly equally strong and always directed downwards. Air resistance is always against the direction of travel and also its effect is strongly affected by the rate of the round.

With a speed of 8.5 m/second (30.6 k/hour, 19.125 mph.) the air resistance is around equally as strong as gravity. Air resistance yet rises or decreases by the square of the speed. This means that a doubling of the speed to 17m/second (61.2 k/hour) signifies a fourfold boost in air resistance. Halving the rate to 4.25 m/second (15.3 k/hour) would bring around a reduction in air resistance to about one quarter of gravity. In the case of fast respond to play an average normal rate would be in the area of 12.5 m/second (45.0 k/hour) which suggests instantly that it’s always the air resistance which is the conquering element in the at an early stage stperiods of the ball’s trajectory. (In the situation of human being documents for counter-hitting (of so many type of shots per minute) an average rate of only around 33kph is achieved).

In the situation of a top-spinning ball the pressure of the spin is at best angles to the speed and also the rotational axis and also as an outcome strengthens the downward pull of gravity. Very strong topspin is of the exact same magnitude as gravity and also the sphere will certainly sink much even more quickly. Keep in mind that a pure sidespin sphere will certainly have actually a distinct arc when watched from over. In the situation of strong backspin the trajectory will veer upwards - here the power of the spin is stronger than gravity.




Of course it is the player’s very own skill and also technological knowledge which will recognize his or her alternative of direction, speed and/or spin. There is however an absolute limit for the all out difficult smash wright here in concept one can utilise a fully directly trajectory.

Below the absolute line of sight the rate facet in all no spin or backspin balls will certainly be restricted as all such balls will certainly call for an arc and some margin for error will be essential in the stroke. The no spin smash is the game’s hardest hit (about 31.1 m/second (measured speed off the racket) or 112 k/hour) and provides the foe the least feasible time to make the rerotate. If balls better than the absolute line of sight are looped rather, this means a slightly safer shot but at a slower tempo. However the challenge in switching from topspin to smash often means that many kind of players choose to spin even in this ‘high ball’ instance.


Under the absolute line of sight topspin is used more than any other stroke as the arced trajectory allows even more and also more power to be fed right into the shot while still retaining a high meacertain of safety via rate. The absolute line of sight is therefore a helpful tool in judging the best stroke to play in any type of offered situation.


- Smash


- Topspin, backspin or counter-hitting through well judged (and also controlled) rate.

Technique for the low ball

Often in the boy’s game even from an early age it is a great concept to job-related through topspin as this offers high rate and additionally a high level of safety. With the help of topspin players can have a comfortable margin for error, a reduced trajectory and also a lower bounce on the opponent’s side of the table.

Backspin through its straighter trajectory frequently often tends to come through nearer to the finish of the table. However in spite of this frequently the optimal of the arc is higher and the sphere can easily kick up after the bounce (there is additionally a reduction of speed at this stage) over the dangerous ‘absolute line of sight’, which leaves the defender open up to a level hit kill. It is therefore vital that defenders take the ball as at an early stage as feasible and also above table elevation. Then they have the opportunity of a low banywhere the net and a reduced ball after the bounce, as the ‘speed’ facet has a tendency to take precedence over the effect of the spin and also the round syoungsters via off the table surface. Also the previously chop will retain more spin as it is in the air for a lesser time between strokes. Length is additionally essential for defenders, either incredibly lengthy or very brief, so that adversaries have bit possibility to smash.

If defenders can introduce a topspin sphere ago from the table then this is a highly desirable variation, especially sometimes via sidespin. There will be a huge difference in between the topspin and backspin strokes and also even the best of attackers will make mistakes.


We must additionally look at the scenario wbelow we face high lobbed balls. Here you will certainly often have actually the chance of smashing from 3 locations, as the round bounces upwards, at the ‘peak’ position or as it is descfinishing (Diagram E). The ‘peak’ position (2) will certainly require somepoint choose an overhead tennis smash and also will certainly bounce with high and lengthy offering the adversary time to play the rerevolve, although the stroke is relatively safe. Killing the descending ball is likewise rather safe (3) but as you make call from better earlier, you have actually much less of the table to aim at and aget the adversary has more time also though the trajectory will be flast.


Theoretically the preferred call must be as the sphere bounces up (1). Here you have actually the possibility to kill absolutely flat and angle the sphere well as you are closer to the net - the foe has exceptionally restricted time to react. The problem can be that you have actually much much less time yourself to study the spin and also to react to any stvariety bounce. This contact is therefore a small more unsafe and also requires practice (a short arm movement is essential in this stroke). An amazing different is to use topspin from an early timing position - even though this is a slower stroke which gives the adversary time it results in a much more curved shot and a ball which drops quickly after the bounce. Other options are the chop smash or a soptimal sphere taken exceptionally at an early stage.


The flick requires some feeling as the round have to be kept as low as feasible over the net and also yet it is tough to produce rate from a brief ball often served via backspin. Good topspin have the right to develop a safer stroke however often it is not easy to accomplish this over the table. To reach maximum speed over the table the flick should be taken at the ‘peak’ of bounce on eextremely occasion, though the late-timed stroke played more progressively deserve to also open up possibilities.

It is possible to feed in about 10 - 15% even more speed into the diagonal flick because of the enhanced distance connected. (Total easily accessible distance 3.1m as opposed to 2.7m)

If you wish to flick even more safely, with a higher margin then this will call for playing the stroke more progressively. Flicking right and also low over the net will certainly lead to a maximum rate of about 8.0m/second (28.8 k/hour) but this would drop to 7.0 m/second (25.2 k/hour) if you wiburned to have a 2cm cushion over the net. Diagonal play would certainly provide the higher number of around 10.0m/second (36.0 k/hour) dropping by 10% (32.4 k/hour or 9.0 m/sec) if the ‘safer’ diagonal stroke were attempted. The flick can frequently be angled harder and also even more easily than the respond to hit as it is taken closer to the net and through less speed on the incoming round. However no amount of training ca boost the power of the flick past what the organic laws enable. The lifting movement (attacking a ball reduced than net height) sets the limit and this can only be get rid of by the production of even more topspin. However before as we have actually intimated this is incredibly challenging in the case of a low over-the-table ball.


If you assume that 2 optimal players take the ball about 20 - 25cms off the end of the table then in a rally the ball would reach average speeds of about 12 — 14 m/second (43.2 - 50.4 kms per hour, directly and diagonal respectively). In the instance of the safe 2.0 cms over the net stroke, speeds would be around 11.0 and also 12.5 m/second. When you compare this via the flick, the last stroke would certainly not achieve speeds in excess of two-thirds of counter play or approximately 10.0 m/second (36 kms per hour).

The supremacy of the Eastern players over the years has arisen mainly bereason they take the sphere early, just after the bounce. European players on the various other hand also take the ball at ‘peak’ or after the top of the bounce. The difference in usable reactivity time provides Asian players a genuine advantage by staying clear of adversaries from coordinating and organizing their best strategies.


The serve can differ a great deal yet the organization rules and also organic laws impose particular constraints. Due to the fact that the serve must bounce from one fifty percent of the table to the other this suggests a minimum upwards and also downwards movement of approximately 34 - 35 centimetres (17 + 17). The time framework is roughly 0.38 seconds for a backspin or float serve yet this deserve to be lessened in the situation of solid topspin. One need to bear in mind that the limit for a lengthy serve right is 2.7 metres yet this rises to 3.1 on the diagonal.

The time limit from bounce to bounce is roughly the very same for a long and brief business. However in the case of the brief serve one have to add the moment from the racket contact to the first bounce which will include 0.15 - 0.2 secs. The full time for a short serve can be as long as 0.6 secs compared via the 0.4 for a long quick serve. The speed for a long fast serve will be extremely equivalent to the speeds once flicking - in between 8.5 m/second (30.6 k/hour) directly, to as much as 10.0 m/second (36.0 k/hour) on the diagonal.


Strong spin presupposes that adequate power has been provided however spin and ball speed are associated and also it therefore adheres to automatically that high rate will certainly even more often than not entail high spin.

The short serve will certainly therefore constantly have a measurable spin which can be reckoned by the variety of revolutions per second, while the lengthy serve deserve to have actually more powerful rotation as a result of the enhanced power input. We don’t constantly endure this on the table as we frequently play via treatment against the short serve, yet also a small lack of touch can lead to a round in the net or a high return. Aggressive returns such as flick and long press do not call for so a lot touch and also are less sensitive to the spin aspect on the ball, therefore it is safer to play lengthy if you have actually learned the approach and also if the opponent’s playing style permits this. Also flicks against backspin can usage the spin currently on the round and also will certainly cause a low dipping shot - long, quick organization retransforms over 8.5 m/second will slow because of air resistance and also this aobtain helps once making use of topspin.

With the assist of inexplicable or deceptive actions the server tries to hide the spin, rate or direction so regarding obtain an benefit over the adversary, lengthening his reaction time or making it harder for him to read the spin. Bear in mind that the variations to be discovered in the use of spin, rate, size and placement will regularly be enough to cause troubles for adversaries and it is vital that your players deserve to use the very same serve in differing methods and execute differing serves through the very same or comparable actions.


After call through a blade (without rubbers) the round will retain on return around 85% of the incoming rate. In the situation of a racket through 2.0 mm rapid reverse rubber the rerotate rate after the contact will just be around 70% of the incoming ball’s pace. For an attacking player the rubber’s job is to preserve the speed as much as possible (a component of the ball’s energy will always be shed against the surface) and also at the same time give the player an excellent opportunity to produce and also differ spin throughout play. It is obviously necessary that the external surconfront of the rubber has actually high friction, while the sponge deserve to differ in hardness depending on whether the player needs more spin or rate.

Harder chisels and sponges offer more speed at the cost of manage while softer chisels and also sponges carry out even more spin and control as there is a longer contact time on the blade (without gluing you shed between 10 - 20% of the rate and spin). The blade additionally has its part to play and also even under the rubber and also sponge it can dedevelop versus a hard hit. One can quickly watch that with a call speed of up to 31.1 m/second (112 kph. or 70.0 mph.) and also a call time of a thousandth of a 2nd, with a sphere weighing 2.7 grams, the influence deserve to be incredibly significant. If the stroke is not played absolutely cleanly then solid vibrations have the right to be developed in the blade through occurring energy losses. An ‘unclean’ hit always offers sreduced speed.

Usually we deserve to say that fifty percent the racket rate contributes to spin and also the other fifty percent to speed. What you acquire in the one element you lose in the various other. When looping versus a topspin round the spin should be reversed which calls for strong friction and also a very closed racket. Looping versus backspin implies that you play via the spin which requirements a lot less friction but a significantly even more open up racket angle.


Ircorresponding of the ball’s motion in the air, the friction and also bounce depfinish on the material features of the racket and also of the table. Although in principle the very same natural laws must use in the time of ball/table contact and also in ball/racket call, here the 2 surdeals with are considerably different, differing from smooth and shiny to sticky through tremendous friction. Another vitally important aspect is that the bat is commonly provided actively while the table’s component is always totally passive.

The power which one imcomponents to the stroke, the movement energy, have the right to be of two kinds, rotational or speed worth. A smash has solid speed value while a loop has a good deal of both values. In the instance of ball/table and ball/passive racket the rotational power have the right to preconquer, dramatically slowing the rate value. Perhaps the the majority of necessary consequence can be that the reversed rotational energy not just returns a a lot sreduced round but additionally one that can transform direction fairly markedly. In the instance of the ‘active’ racket a new movement energy will be established.

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The result which will happen between the sphere and the table is partly bereason of the bounce N (influence speed and also angle) and the spin T (amount and type). Tbelow will also of course be power losses (a reduction in rate of around 10%). The outcome will certainly be a bounce which can reach a elevation of approximately 70% of the trajectory’s high suggest in trip.

The float sphere will certainly shed rate after the bounce however will certainly obtain a weak topspin due to the bottom component of the round being hosted by the table and also the peak part rolling forward (Diagram F). In the situation of strong topspin the sphere will gain forward power and this rotational momentum will certainly be converted into extra speed (Diagram G). The speed of the ball’s activity forwards will rise. The result will certainly be a bounce of less than 70% of the greatest allude in the trajectory, with a lesser spin but an boosted speed (in the range of some 15 - 20%). The backspin round is equivalent to the float sphere - however the significant difference will be the spin aspect which will certainly have actually as much impact as the frictional attributes of the table’s surface will permit. Often it have the right to be a question of the round ‘sliding’ via. Otherwise tright here will certainly be a clear ‘braking’ result after the bounce and the ball will slow, kick up a little and hang in the air (it deserve to frequently kick up over the absolute line of sight).


Sidespin has actually the rotational worths at ideal angles to the table’s surchallenge which indicates directly that as the suggest of the axis is in contact through the table, tright here is bit or no loss of spin. The round therefore comes with through maximum retained spin.

The friction in between the sphere and the table will certainly reach a maximum of approximately 20% of the impact force between the round and the table - then skidding occurs. In comparikid the friction between the ball and also the racket is exceptionally a lot more powerful and will reach levels of 50% or more. In the situation of a passive stroke wright here the racket scarcely moves then the effect of the spin against the surchallenge will be excessive.

Reverse rubber is very sensitive to spin and also the racket need to be at the right angle with recommendation to the incoming spin and rate. A great deal of topspin will require a very closed angle yet if the speed is likewise high then the angle will must be opened up up. In the situation of the ball’s contact via the racket we are came to through two types of power. N = Common power which is composed of the bounce and also the rate of the ball and also T = Tangential power which counts on the spin and also the frictional features of the racket.

‘Braking’ or frictional pressures have the right to have actually a major result on the rotational worths (spin) and also the rotational power can be adjusted, exhibiting itself as an increase in speed or as a dramatic adjust in direction.

The loop is commonly executed via maximum racket rate and as thin a call as possible. The harder one endeavours to strike the ball (via a closed (topspin) racket or open (backspin) racket) then the even more spin one will accomplish together with rate. Always bear in mind but the old cliché - ‘What one gains in spin one loses in rate and also vice versa’.

Interesting impacts deserve to additionally be achieved as soon as one contacts the spinning ball at one of the poles wbelow tright here is little bit or no spin - the spin will certainly remain on the rerotate sphere however often in a completely unexpected create. This is due to 2 various axes trying to assert themselves at the very same time. A loop versus a sidespin round will lead to a topspin rerotate via a sidespin kick.


Obviously the further you earlier amethod from the table the more time you will need to prepare and also the more time to set yourself and also hit the sphere harder. However before equally the adversary will have actually more time (Diagrams H and J). Both display how the sphere loses speed over a distance. If two players are each three metres ago the full distance between round contacts is around 9 metres and the ball will certainly sluggish with the air — this offers over fifty percent a 2nd to react which in the case of two fit, skilful players will mean that it will be hard to outmanoeuvre the adversary and also win the suggest.


Diag. H. Choose your initial velocity, say 20 m/second which provides you a mark of roughly 0.1 seconds on the curved line and also a number of 3 on the baseline. Forobtain the figures to the left of the 0.1 and work through the right finish of the curve. After another 0.2 seconds (0.3) the distance is 7.0, so the round has actually travelled 4.0 metres (7.0 - 3.0) and also the rate is dvery own to about 11 m/second.


As we deserve to see from (J) there is a huge distinction looping close to the table and also executing a comparable stroke three metres earlier. If we feed in an initial rate of 15 m/second, sphere (1) will reach the other end of the table in 0.2 of a 2nd or slightly much less and will then have a speed of 10 m/second - round (2) on the various other hand also will take roughly 0.5 of a 2nd and the rate will certainly have dropped to 7.0 m/second. We should also bear in mind that also at fairly slow speeds, say an average of 40 kph, the ball will certainly cover the length of the table in around 0.25 of a 2nd which is the approximate limit of humale reactivity time for the average player.

There are obviously several advantages in playing closer to the table which many optimal males are currently coming to appreciate in the structure of our much quicker contemporary game (the women have supplied these advantages for many years).

The angle of play increases.The rate of play boosts.The time to play decreases.

These elements mean that the adversary hregarding cover even more of the table and even more ground in a lesser time and hregarding react at a higher rate (the time frame deserve to even more than halve). With accessibility to indevelopment on time, distances and also rate (in relation to the ball) one have the right to quickly relocate into the optimum place to make the best use of time and also press the adversary. Equally such understanding provides perception right into one’s very own capabilities and exactly how these need to build.


Explosive speed is an inherited characteristic and players that don’t have actually it are rather limited in what they have the right to perform to train up this aspect. However tbelow is nothing to speak any type of player only using those trends which provide most economy of activity. It’s elementary for example to understand also that quick play requires short strokes so that you can recoup for the following sphere (not so short however that you fail to play ‘through’ the ball). If in our contemporary quick game you are assaulted difficult and also have no time, then you must be satisfied with the block return.

Racket recoincredibly is especially crucial and also it’s vital that the racket retransforms to the neutral place after each stroke so that you are prepared to play FH or BH on the following sphere. It is equally vital that the elbow drops dvery own after the stroke (specifically the BH counter) so that the forearm is in the finest feasible position to relocate in either direction.

The ultimate style of the player will dictate which kind of activity trends he or she should usage. Close to the table blockers will usage many type of one-step activities or tiny jump procedures. Strong loop players will certainly inevitably usage the cross-action to reach the wide ball and defenders have to train at relocating in and also out. However via the contemporary game both close and deep, movements which retain a square position are preferable. Movement is among the the majority of instrumental components of any type of young player’s development and also yet exceptionally few countries in Europe occupational constructively with footoccupational fads at an early age. It is especially crucial that you create a pattern through a young player that have the right to thrive via the player, (can a sidestep pattern be easily emerged into a cross-step?). It is additionally a priority in the ‘modern’ game, wright here we have actually limited time that footoccupational is economical, one massive action is preferable to many kind of small ones.

Among the world’s elite (especially the Eastern players) the FH is still the leading stroke and many males players will still move more in order to carry this wing right into play. (Among the height European men because of the increase in the fundamental minimal speed many kind of now usage the BH from the middle or even from the FH side against the serve. It will certainly be exciting to watch if this tactic, which has actually been prevalent amongst the womales for many years, will certainly end up being the norm in the men’s game).

Perhaps below a warning have to be issued to womales trying to usage the FH over the entirety table as some height males carry out. The women’s game is quite much faster as they stand also closer to the table, hit the sphere previously and flast. Often they have less time to relocate and to react between shots. Also all at once their physical capabilities have the right to be reckoned as between 15 - 30% lower than the male. These components deserve to make the difference in between success and also failure at optimal level.

For a optimal player to execute solid topspin from FH and also BH corners with FH and also BH consecutively takes around 0.6 of a 2nd. However before to carry out the very same via just the FH wing will take almost 1.0 second. This is fairly a huge time distinction at height level. FH play over the entirety table is asymmetrical (by this we mean one-sided and unwell balanced movement). Symmetrical play is clearly remarkable from the point of view of economy of activity, the just downside being that the BH topspin is mainly less effective than the FH.

A adjust to even more symmetrical play requires that the BH topspin be of the same top quality as the FH. This deserve to be achieved by use of what we speak to the tennis BH. Here through a quarter rotation backwards, taking the ball off the left hip and also using great rotation and extremely rapid forearm action, the stroke can be upgraded to a comparable power and rate as the FH. Certainly in the future it is ending up being apparent that in the light of the rate of the modern-day game, play will end up being even more and even more ‘symmetrical’ and that this will be the method forward.


A stroke can be executed through a large radius (a straight arm through forward movement) or with a small movement (flick of the wrist). If you use a big action then a small mistake in ‘timing’ will have actually bit significance, but via a small motion the resulting error in placement will be incredibly noticeable. Use little activities over the table and the large activity additionally back wright here you need even more power and precision of placement.


In the instance of any kind of stroke wbelow an arc is offered we have the right to have actually a positive or negative arc (Diagram I). The positive arc follows the outgoing trajectory of the ball much more closely and also as a result has actually a higher safety and security margin. The negative arc places much greater demands on specific timing. However in the instance of the loop against a backspin round wright here the racket angle is a lot even more open up the benefits or disadvantages are not so critical.

Many type of players think that it’s safer and also more natural to have actually a negative arc with the BH topspin and also especially where the feet are more parallel with the finish of the table. However for those who desire to work-related with the ‘tennis’ BH it’s important that they have the very same positive arc on both wings and also don’t need to adjust from one to the various other.


Whether it is a issue of standing right, relocating in the ideal method or placing the sphere in the most advantageous position, one have the right to have a good deal of aid from pure geometrical evaluation. Many players for a start will certainly want to cover about 60 - 65% of the table with the FH side as they deserve to reach further on this wing, and also 35 - 40% via the BH.

From the suggest of watch of recovering to the a lot of valuable place relative to the angle of play, you must assess the total angle easily accessible for the opponent’s usage and also move into a place wbelow your ideal shoulder is on the centre line (the bisecting line). Obviously as soon as playing the FH from the BH edge playing on the opponent’s BH diagonal provides the most helpful rerotate angle.

However through the FH serve from the BH corner this deserve to be put to either corner - it is only important that you move to cover the rerotate possibilities the immediate after ball contact is made.

In doubles play the exact same geometry applies - the just distinction is that the one that plays the sphere doesn’t have to take the rerevolve. It is important to area the round in an beneficial place for your companion. A right- and also left-handed player complement each various other well in this situation as both deserve to frequently usage the FH a lot of of the time. In doubles it is wrong to always attempt to go back to a normal prepared position just as it is not profitable if both partners finish up wide out on one edge or the various other.