The kind of tennis strings (guts)

 

 Today, I will write about tennis strings. String is something like fiber formed on in length and breadth to a racket. And it is an important part coming in contact with a ball. There are various types of things varying in material, a shape to such a string. So I will write about it.

                           

MATERIAL

 A string has three kinds by material. It is a natural string, a nylon string, a polyester string. I will explain turn them.

 

 The first is a natural string. It is the nature material that most are made with the bowels of the cow. A feeling of hold, a feeling of batted ball is very superior. From a beginner to a professional player, I can recommend it to anyone. However, a price becomes higher than other strings because it is made with a nature material. By the way, the quantity necessary to make natural string for one racket seems to be 3 cow big shots.

 

The second is a nylon string. Most of the general people use this nylon string. Nylon is scientific complex material and called “Polyamide” formally. The touch feeling when people hits when people hits the ball because it is a relativity tender string and is high repulsion is superior.

 

 Finally, it is polyester string. Because, as for this string, there are not many repulsions a string by hardening; of the ball become slightly relatively controlling flying. It is a string turning to a player and the hardware hit player who it is hard to be sharp because it makes much of the durability, and hang a spin. However, I cannot recommend an elbow and a wrist to a weak person because a shock is slightly bigger. In addition, I cannot recommend it to a person to use too much for a long term because the endurance of the tension is very low too.

 

SHAPE

 It greatly distribute the shape of the string is two kinds.

 

 The first is called multifilament. It bundled up limitlessly minute fiber and had the structure that was near to natural string. It takes time for the manufacturing method, and there are many products which are more expensive than mono filament (I explain the monofilament later). It is most suitable for a person making much of a touch and a person making of serve and the volley. The durability is slightly lower than monofilament, but is recommending for the person who does not finish remaining. I recommend it to the person who comes to have a pain in an elbow and a wrist immediately.

 

↑multfilament

 The other is monofilament. A bit big core thread is set in the center of the string, and a thing filament generally means a string of the structure that wound a rather thin thread around the circumference. It features a feeling of sharp batted ball. The price is set low, and it may be said that it is a string having highest utilization in the public.

 ↑monofilament

 

 How is it? Not only a racket and the ball but also the string is one of the important factors in the tennis.

 

Then it is the next time again. Good-bye.

The history and characteristic of tennis ball

 Hello everyone! Today, I will write about history of tennis ball. In addition, I describe the difference with a ball used for other competitions.

 

 As a premise, the tennis ball greatly separates two kinds. It is a rigid ball and a rubber-ball. I write it as these two histories and characteristics each.

 

At first I will write it about a rigid ball. It was from the 18^th century that tennis came to be carried out in form like the present by a former article, and the previous tennis ball seemed to be the ball which I filled with things such as the animal hair and sawdust in cloth and skin. This is said to be the forerunner of the rigid ball. As for the current rigid ball, the surface is felt and rubber and air is in the covered inside. It is said that the ball made of the rubber like the present came to be made in the 1870s. It became the ball which it was easy to control by making it with rubber and felt. Furthermore, people changed the seam which was outside sewing into inner sewing and became the ball which took a bad hop, and was hard to bounce. It is the rigid ball with such a characteristic, but, in fact, it is divided into two kinds of a game ball and the practice ball by a difference of the pressure of air included inside. The game ball called pressure ball. This is double the pressure in the ball approximately two of the atmospheric pressure and raises the repulsion of the ball. The practice ball called Non-pressure ball. The internal pressure is the same as atmospheric pressure, but bound as same as a pressure ball because it is only slightly thick. Some feeling of batted ball is heavy, but there is an advantage to be usable without repulsions changing even if they leave you unattended for a long term.

 

Next, I write it about a rubber –ball. There is the rubber-ball is made from rubber with a ball used in soft tennis. And air enters inside. It is defined that a color is white or yellow, as for the diameter, 6.6centimeters, weight are 30 grams-31 grams. In the coat, the bottom end of the ball drops it from an altitude of 1.5 meters, and it is decided that 70-80 centimeters bounce. It is told that the rubber-ball Japan. It is said to be origin people make a ball with rubber in substitution for high-quality felt in those days, and to have played tennis in the late 1800s when tennis was handed down to Japan. A person called Gendo Tsuboi gets a idea from a rubber ball that Japanese traditional toy and makes it, and it is informed that I came to be able to play tennis willingly in Japan.

↑pressure ball

↑rubber-ball

 

Might you feel such history and characteristic on the ball which one of the tools of the tennis was?

Next articles, I will write about tennis gut. See you again!

The change of tennis racket

 

 Today, I want to write about tennis racket. Tennis is a competition to perform with a racket as everybody knows. However, the old tennis may be greatly different from the present tennis that everybody images. So today, I write about tennis rackets changing.

 Tennis racket changed materials, a large area of the head size (the area that gut is put on), frame thickness increase, frame lengthen increase, and performance largely improved.

At first I will look from a point of the material. The early tennis racket made of wood. It was sometimes made of bamboo. It was said that bamboo had better flip than a wood. However, the racket that made of wood or bamboo is heavy and easy to deterioration by humidity, temperature and secular distortion. To correct there problems, the material of the racket changed steel, aluminum alloy, titanium, graphite, resin or including the fiber in resin and the composite materials which put resin different in the property together. With improvement of the material of the racket, these problems are solved. Furthermore, of the ball flew, and the speed improved drastically, too.

Second, I will look from a point of the head size. The old racket had a smaller size of the aspect at approximately 70 square inch than now. By the way, current head size is 95-120 square inch. The reason that head size came to have a big is speed of the serve in particular rises, and the volley is stable.

Third, I will look from a point of the frame thickness. The thickness of the frame in the days of the wood racket is about 17~21mm, and 22~26mm becomes mainstream now. A racket such as 35mm was correct in the thickness racket golden age. Generally, the speed of the ball rises so that the thickness of the frame is warm. It thickens to be similar for a child and old person without the power.

 Fourth, I will look from a point of the frame lengthen. As for the length of the current racket, 27inch is major. The old racket had a long 1.5 or 2.0 inch than the present racket. If racket is long, serve in particular becomes fast by centrifugal force. Because other shots use centrifugal force, the principle of leverage, naturally it becomes fast. However, control is worse when racket is long. So now, we can hit the ball fast by a change of the material, they do not lengthen a racket.

  Finally I will write about unique tennis rackets. I think you image the grip of the tennis racket to be only one. But the racket having two grips called the double handle grip (or natural power grip) exists. In fact, such a racket was born because the number of the grip was not shown in the definition of the tennis racket and might make a grip several of them theoretically.

↑double handle grip racket

↑wood racket

↑major racket

 

 How did you like it? Might the tennis racket understand that it existed after various changes now? By the next article, I write about a tennis ball. See you again!

The kind and characteristic of tennis court

Today, I want to write about tennis court. Of course I think that you know the tennis court. However, a tennis court has kind and characteristic you do not know. So I will write about kind and characteristic of the tennis court.

~kind and characteristic~

 The kind of the tennis court is distinguished in used material mainly. There are six main tennis courts, they are called omni, hard, clay, carpet, en-tout-cas and glass court each. High speed and bound of ball are different by a court. Let’s explain each court.

(1)  Omni court

Material: Artificial turf with sand      Ball speed: Slow     Bound of ball: Low

 The ball bound as slip and spring is bad. There is relatively little irregular, and is easy to use it very much. There are few burdens to a foot and it is relatively cheap. Furthermore, it is strong in the rain. So it is used by high school tennis club and society tennis club.

(2)  Clay court

Material: Soil      Ball speed: Slow     Bound of ball: High

 The ball jump while slowing down after bouncing. The bound is high. Clay court maintenance is difficult. In the rough clay court, irregular appears one after another. Because the maintenance cost of the tennis court is considerably cheap. So it is used mainly by student tennis club.

(3)  Hard court

Material: Concrete      Ball speed: Fast     Bound of ball: Very high

 The ball bounds very highly. Because the burden to a foot is considerably big, the person with the uneasiness should stop it to a waist. By practicing with this court, I can catch fast balls. Because management is easy, hard court is seen in Japan for rent court.

(4)  Carpet court

Material: carpet     Ball speed: Fast     Bound of ball: Very low

 Carpet court is seen at an indoor tennis school and a relatively rare tennis court. If there are not exclusive tennis shoes, you slip and in danger. Because a ball does not bound, the ball which it is easy to hit comes for the woman. Because it is easy to fall down, you have to careful about steps.

(5)  Glass court

Material: Glass     Ball speed: Very fast     Bound of ball: Low

 The ball jump to slip than Omni court. It is the court of the highest speed. Because of glass exchange, maintenance cost is very expensive. So you can rarely see it. For the high maintenance cost, there is many it in the developed country.

(6)  En-tout-cas court

Material: Porcelain clay     Ball speed: Slow      Bound of ball: High

 It is a rare court made with the powder of the brick. A ball is easy to bound, but stalls after bouncing. There is much irregular. Drainage is good, and the ground is kinder to a knee and a waist than hard court softly. It is used most in France, and the French Open Tennis Championships uses this court.

↓En-tout-cas court

↑Carpet court

 

 

 

 

There are various kinds even if I say tennis court. When all of you will watch a tennis court in future, please pay attention to material.

 

That’s enough for today. See you next week. Bye-bye.

Structure of the world rank

At the Beginning

Today, I will write about professional tournament ranking system. Do you know World Ranking in tennis? In 2012, number-1 ranked tennis player is Novak Djokovic. Then how is it decided? Organizations managing the ranking in men and women are different. It is a group called the ATP(Association of Tennis Professionals) to manage the world ranking of the man. On the other hand, it is a group called WTA(Women’s Tennis Association ) to manage the world ranking of the woman. But the structure of both is the almost same. Now I explain the structure in case of the man.

Ranking system

 The ranking of the man is managed by ATP as I explained it some time ago. Two ranking systems have been used by the ATP to date. They are 「Entry ranking」 and 「Champion’s race」.

First, I will write about Entry ranking. Entry ranking is method to decide Annual ranking in total point of the high rank 19 games that I participated in during the past 52 weeks. Entry of the points will be detailed later. Because this method becomes the average of results of the past one year, even if there is the bad meeting of results, it does not affect ranking at all. So it is unpopular among some players.

 On the other hand, Champion’s race system which began in 2000 is all players start from 0 point. And it is a method that a point is added to every participation meet and decides annual ranking. For example, the player who put a good grade in a meeting to be held at the beginning of the year, he naturally become high-ranking of the champion race in the first half of the age. This system is plain and clear. However, there is too criticism to be short because only the occasional force is reflected by ranking.

Both methods have good points and bad points, too. Entry ranking is used by the singles again as general organization from 2006. In addition, as for the young player younger than 16 years, they limited the number of the meetings that they can participate in the year.

Introduction about points

Well, from now on, I want to explain structure of the entry of the point. The professional tennis players can obtain the point by winning in a meeting of the tennis, but the quantity of the point which to be provided changed by the kind of the meeting to participate in. Look at two below figures. The first figure showed the rank of the meeting. There are many points to get by meeting of the one on the figure. The second figure showed whether several points were provided in each meeting. For example, I can get 180 points if I win to best 4 in a meeting of the ATP500 series. The world ranking makes ends meet by adding up such a calculation for 52 weeks.

 

Next article, I will write about the kind and characteristic of tennis court. See you again!