Tennis court floor material
I. Synthesis of Plastics * * * *
Representatives are Melbourne's Australian Open Center Stadium and Miami. 1988, Melbourne transformed the site surface into a hard ground, and covered it with a layer of rubber, commonly known as ReboundAce. This kind of rubber floor has excellent elasticity, and the ball bounces high after landing. At the same time, because the surface elastic coefficient k is small, the interaction time between the ball and the ground is long, similar to the soft ground. The rubber surface is also mixed with plastic particles, which increases the surface friction coefficient μ. The combination of the above two factors makes the ball speed of rubber field relatively slow.
Second, the concrete * * * concrete * *
The representative is the Ashe Stadium of the US Open, which is the venue of the US Open series. This is commonly known as the cement yard. It's just that the cement field we play is bare, and there is a thin plastic covering or colored paint on it during the regular competition. The height and speed of the ball rebound are determined by the nature of the cover. This kind of court is the fastest among all the hard courts. Because the elastic coefficient k is very large, the vertical component of kinetic energy is greatly lost, so the rebound of the ball will not be too * * * higher than that of the plastic court such as the Australian Open, and because the surface is relatively smooth, it is obvious that the ball rushes forward to the plastic court and the earth obviously stops * * *.
However, it must be said that this kind of court is also the most uncomfortable court, and it is the main reason for players' lower limb injuries. Although it is more ornamental, we fans should not forget the players' feelings while enjoying the elegant Internet.
Third, carpets.
Major stadiums in indoor seasons, such as the Paris Masters Cup and the year-end tournament in Germany in the 1990s. Compared with the first two venues, China fans may be unfamiliar with carpets, watch less and play less. If the plastic is hard, the carpet is hard like grass. But the gap is still obvious. First of all, the foundation is flat, the carpet efficiency is uniform, and the ball bounces regularly on it. There is also a lot of friction on the carpet, and the speed of the ball will be slower than that of the concrete floor, but the ball will bounce very low on it. Fans watching the ball may watch it slowly, but the batter on the court feels that the ball is a little forward. Therefore, there is often a trump card of 160 km on the carpet, and those who serve well, especially those who hit the ball skillfully, have more advantages. At the same time, the ball bounces low, and the force must be exerted from bottom to top when hitting the cross ball, which is not conducive to suddenly falling over the net. In addition, the ball speed is a little slow, so surfers have enough time to choose the displacement position in front of the net, and the success rate of volley in front of the net is the highest. Baseline players can also play well here, but ordinary clay players are not suitable.
Fourth, grassland.
The representative figure is Wen Zhangying. This is a magical venue, an expensive venue, an elegant venue, a venue that is about to disappear. On the one hand, there are economic factors, on the other hand, fewer and fewer people are familiar with it.
Grass has the lowest friction and the lowest bounce is 3/4 of that of hard ground. The ball slipped obviously after landing, which greatly reduced the time for players to prepare for hitting the ball. At first, the grass cover was uneven. With the progress of the competition, the grass roots and land are exposed where the ryegrass falls off, and the friction here will become more and more serious. In addition, the foundation is uneven. Cutting on the grass is more threatening than other sites, but it is not easy to intercept it on the grass.
The biggest advantage of grass is to infinitely amplify the power of serving. It's also 180 km serving here, so it's much more difficult to receive the service. The friction velocity loss of the ball passing through the grass is very small, and the rebound height is still low, leaving the receiver with little reaction space.
Verb (abbreviation of verb) soil yard
Broadly speaking, it includes real sandy soil sites, sites made of similar materials and synthetic sites. The correct name should be soft ground. Although the cost of construction and maintenance is quite expensive, the soft feet and the consequent protection of players have made this kind of venue popular again recently. The earliest earth yard was built of sand. Low cost and comfortable land. Now it is also widely built in underdeveloped areas such as Latin America. But the drainage of natural land is a big problem. At the beginning of this century, Europeans invented the quick-drying site, that is, spreading a layer of broken bricks or volcanic ash on the surface of the site, so that the water will seep down quickly and the surface will dry much faster. In relatively dry southern Europe, the thickness of the ground cover is relatively thin.
On the other side of the ocean, Americans invented the green soil field, that is, crushing the green stones naturally produced in the local area and laying them on the surface of the field, instead of using brick powder as in Europe. These two kinds of venues are now called ash yards. In areas with heavy rainfall or poor underground seepage conditions, drainage can be solved by building underground drainage systems; On the contrary, in arid areas, underground irrigation systems need to be built.
The third kind of "earth yard" is a plastic yard, and the surface of the yard is paved with synthetic materials instead of natural materials. Although the cost is high, the maintenance cost is extremely low, so there is no need to consider the drainage problem. Moreover, the roughness of the ground can be achieved by increasing or decreasing rubber particles, and there are many choices of colors. The speed of this kind of stadium is not very fast, which is determined by the thickness and roughness of the surface layer. It is suitable for both surfing the internet and baseline.
The benefits of playing tennis
1, playing tennis can exercise the brain's reaction ability.
Tennis is a whole-body fitness exercise. When intercepting the ball, you need to run, jump and wave your arms quickly according to the position and direction of the ball, which can effectively exercise the brain's reaction ability and enhance the coordination and flexibility of all parts of the body.
Playing tennis can improve physical fitness and muscle strength.
Playing tennis will * * * shoulder muscles and biceps brachii and triceps brachii, which can effectively enhance the strength of shoulder and arm muscles. In the process of fast movement, it is necessary to coordinate the whole body muscles, especially the leg muscles, so as to get effective exercise.
Playing tennis can enhance physical fitness.
Playing tennis can promote blood circulation and improve metabolism in the new city. When exercising, the oxygen demand increases, and it can also * * * the respiratory system and enhance the cardiopulmonary function. In addition, playing more tennis can also strengthen bones and muscles and promote bone growth and development.
You can lose weight by playing tennis.
Tennis is a systemic aerobic exercise, which can quickly burn fat in all parts of the body. According to some data, playing tennis for an hour consumes 420 calories, which is a high-intensity weight loss exercise.
What should I pay attention to when playing tennis?
1, be careful not to be hit by the ball when picking it up.
Remember, don't run to that court when others haven't stopped practicing the ball back and forth! Not only out of courtesy, but more importantly, protect yourself or your eyes. Because being hit by a ball is still very serious.
Be careful not to be hit by the racket when hitting the ball.
There is something wrong with the swing, especially when the left hand fails to catch the racket in forehand stroke, and the arm swings too much, which leads to the fracture of the brow bone and nose bone of the racket head and the knee injury when serving. The solution is to do a complete action. And a racket as cool as a star. The racket doesn't relax when it touches the ground, but it hurts the wrist. There is also a kind of racket that bounces up and hurts itself when it hits the ground. Remember that the racket is held by hand, preferably with one hand.
Be careful not to step on the ball
The amateur twisted his foot and someone stepped on the ball. So remember, make sure there are no balls on the ground around you! Some girls, in particular, often can't hold a few balls in their pockets, so they put them on the bottom line around them. Aren't balls and feet easier to step on? Remember in the future, when there are no pockets, put the ball on the back of the barbed wire.
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