When the tennis ball is served, the paddle surface is controlled at the moment of hitting the ball

When throwing the ball, relax your whole body and hold the racket tightly the moment you hit the ball.

The most important thing is to maintain the balance of the body when serving, and do not destroy the balance of the body for the sake of large (bending, arching back, vigorous jumping, etc.), which will not only fail to send strength, but also cause the dessert to be inaccurate, or as the landlord said that the paddle can not be controlled, which is commonly called"overhitting"(Excessive force).

It is recommended that the landlord can start to practice serving from small movements, slow down the swing speed, and experience the feeling of controlling the paddle surface and the direction of the serve, and it feels good to feel that it is coming.

The above two have already said a lot, and I would like to add that whether it is serving or hitting, it is not about the wrist force, but a coordinated and coherent movement of the whole body. If you say that you can't control the slap, do you feel that your grip strength is not enough? Do not hold the racket too hard.

Hold the racket tightly and only force it at the moment of hitting the ball!

Although serving is related to power, the key is explosiveness, and it is definitely not a problem of your strength!

Continental grip, while hitting the real ball, there is an inward wrist movement! It's best not to have too much strength when practicing, but be sure to get the rhythm right!

There is no such thing as insufficient grip strength, and it is not entirely a matter of wrist strength, when serving and whipping the ball, the wrist should be rotated from an outward valgus to an inward rotation, and it is necessary to have good flexibility to not hurt the wrist!

Do more stretching exercises on wrist flexibility and strength!

At the moment of hitting the ball.

Tighten your wrists and clench your racket.

Increase the friction by increasing the pressure.

But don't be too stiff without the ball.

This will hinder your ability to perform throughout the exercise.

Hitting the ball is the action of whipping, and the most important thing is the stability of the toss and the balance of the body.

Upstairs is right. There is also a lot of contact on the serve. In the past, the coach said, you have nothing to do with sending two boxes of balls every day, but if you can't send it, find me, haha.

Error on serve.

The following are service errors:

a If the server violates the rules.

7) The serve is invalid.

After the serve touches the net, it still falls into the opponent's service area; The receiver is not ready to receive the ball; Both should be re-served.

8) The position of the server At the beginning of each game, the ball should be served from the end line of the right area, and after scoring or losing a point, the ball should be changed to the left area of the serve. The ball should be sent over the net and into the opposing opponent's teeing area, or in the line around it.

9) Time to serve The server should not serve until the receiver is ready. If the latter tries to hit back the serve, he is considered ready. However, if the receiver makes one he is not ready, he cannot claim a mistake on the serve because the ball does not touch any part of the field within the fixed limits of the serve;

b. If he fails to hit when he tries to play;

c If the ball is sent out and touches a fixed object (excluding nets, centre belts or net belts) before touching the ground. Yours is a b-question.

It doesn't count, it can be reissued.

1 time doesn't count... It seems like it's 3 times...

The first serve is counted as a mistake and the second serve is directly counted as a lost point.

Tennis service errors are subject to the following provisions:

1. Missing the ball;

2. The ball sent out touches the fixed object before landing (except for the net, center belt and white cloth on the edge of the net);

3. Violation of the rules of the serving position.

After the server has made a mistake on the first serve, the second serve should be made in the original position.

In 2013, the International Tennis Federation revised the rules so that wiping the net no longer affects the success of the serve, and is judged by the point of the ball after it touches the net. If the ball goes into the net or falls outside the diagonal teeing area, the serve is wrong; After the serve touches the net, the repentant still falls into the opponent's service area; The receiver is not ready to receive the ball; Both should be re-served.

Therefore, before the serve touches the effective area, the racket is out of hand and touches the net is considered a mistake.

After reading the answers of so many friends, I found that what they said was good, but I personally think that none of them are the key, I also had this problem when I was a child when I was learning tennis, and then I asked the coach to help correct it, and there are three reasons for this problem:

1. The height of the throwing ball is not enough, the height of the throwing ball should be the action of standing up straight with the body and holding the clap hand to hit the ball at the moment of serving, then you will find the highest height that the body can reach, and then 5 cm higher than that height, which is your ideal throwing height.

2。There is no squat, which will cause the body to not be comfortable and rush to hit the ball.

3.The third point is the most important point, and many people have this problem, first of all, you should understand, what is the purpose of doing the action of turning the head down, many amateurs are symbolically doing it, in fact, it is not right, when the head is sinking, in order to allow us to better use the power of the waist and the power of the leg push. When serving and throwing the ball, your body should be perpendicular to the net of the court**, and your body should be facing the net after serving.

The above is the principle, let's talk about what to do: after the head of the racket falls, then your body should be squatting, and it is perpendicular to the net of the field **, and then it should be like a whip, with the rotation of the body sinking the head of the racket behind you also follow the rotation of the body to animate a small half-arc circle, and finally throw the racket out, if you are the right hand to grab the racket, after hitting the ball the racket should be swung to the left side of the body with inertia, and at the same time the left hand has the action of holding the abdomen.

If you do this, your problem is basically the same, but you still have to practice more, I suggest you look at Federer's serve, there is a slow release is the best, his movement is more recognized standards, and it can also help you understand the third step I said, as for what Roddick is okay, his serve is good, but the movement is basically not standardized, not suitable for people to learn (like who will follow Nadal's movement to hit the forehand).

That action is generally called scratching the back, which is like scratching the back.

There are two main reasons for your problem, the first is that you are not familiar with the back-scratching action, and it feels awkward to do; Second, the rhythm of the toss and swing is not right, resulting in not enough time to complete the back scratching action.

How to improve: It is recommended to start with a no-ball imitation exercise. That is, he does not hold the ball with his left hand, but pretends to throw the ball, and completes the entire serving action according to the specifications.

In this way, because there is no ball throwing to distract your energy, you can focus on completing the back scratching, and then practice with the ball after you are proficient in the off-ball action to experience the rhythm of cooperation. In addition, it is recommended that you can get closer to the net when you start practicing with the ball, such as standing on the service line, so that the ball is easier to cross the net, and you can use more energy on the action, and reduce the worry of not being able to reach the net. I hope my answer is helpful to you.

First, when serving, first of all, don't think about using your arms to serve, that will make you move your arms too early, which will cause your movements to be too mechanical, imitative and incomplete.

Second, when serving, you must first kick the ground with your legs, turn your waist, turn your shoulders, and finally whip your arms and wrists, so you must have the right order of force, starting from your feet, so that the racket will naturally fall off and scratch your back, and of course you will have strength.

3. If it really doesn't work!! You can play the ball by pulling the racket on your back in advance, then throwing the ball up to hit the ball, and then slowly smoothing the movement to the end.

It is recommended that you practice dumbbells because it is heavier, so you will definitely fall off and then practice with a racket. The first can be linked to strength, and the second can be linked to action. Kill two birds with one stone.

You can use the continental grip method to hold the racket handle with two fingers, that is, the thumb and the index finger, so that the racket head will hang down naturally, and then lift the racket head, do not hit the ball when practicing, so as to change your habits, and then use one hand, slowly change, of course, you still have to practice more. That's all that matters.

Explain that the action of drawing an arc behind your back is not complete, so you have not accumulated more strength If the action is not fixed, you can try to throw the ball a little farther away from your body, and then use your body and wrist to press the ball.

Haha, look at your height...

Generally, people who are tall 175 use flat shots, and below 170 use side spin or top spin This is not necessarily, but the success rate will be a little better!!

You said that the head down is not done, it is estimated that there is only a spin ball, to correct the words is very simple, like a regular serve, pretend to take the ball left and right and throw it up, the right hand then pretend to hit the ball, try to swing the racket up, choose the best hitting point, and then swing down to the lower left corner!!

If you want to serve well, the main thing is to use your feet and toss.

I've been playing for a year and a half, and I've been training every day at school, and I've been to a few races!!

Personally, I don't quite agree with the opinion upstairs. The serving action of the famous player combines its own characteristics, and it is easy for amateurs to blindly imitate it. In response to your question, I think you can do the following:

1. Throw the ball a little higher. Throwing the ball too low will shorten the time it takes you to do the action, resulting in incomplete or even incomplete actions for some actions. There may be a lack of stability at the beginning, so you can practice throwing the ball without holding the racket to improve stability.

2. Don't exert force. The serve of tennis is a complex process of power transmission, and the direct result of not doing any of the links well is that the power is used well, but the ball speed is not fast. When I watched Federer train at the 2010 Shanghai Masters, I found that he didn't use a lot of effort to practice his serve, but he still hit the ball at a speed of about 160 kilometers per hour, because his strength is the best for his whole body, not just the strength of his arms or shoulders.

When practicing the serve, it is important not to just look for speed and not pay attention to the movement, when the action is in place, the ball speed will naturally increase. Therefore, don't exert too much force in the practice of serving movements, and when the action is skillful, the ball speed will naturally increase, and then you can use your strength to play.

I think, one: you should practice the rhythm of throwing the ball and swinging the racket.

Two: Also, you need to bend your elbows slightly to shorten the swing distance.

Then you're okay to practice a few more times without the ball, and then try to practice with the ball.

Contact, continue to practice this action with a racket, practice in front of the mirror if possible, and do this action for a long time, people's physical habits, there is a saying that habits become natural.

You're talking about scratching your back, but in fact, that action is not so important, and the serve is all based on your own habits and body coordination, and you see that the serving action of the top players is not the same.

It may be that there is not enough time to complete the action, so it is recommended to: 1. Throw the ball higher. 2. Practice this complete serving more often to increase proficiency and flexibility of the shoulder joint. 3. In addition, there is a small opinion, colleagues who throw the ball high can also throw the ball slightly forward.

It is recommended to take a look at the tutorial more... There are conditions to find a coach to guide you. Or you can take your own action camera footage. Then take a closer look at the process behind the process behind the improvement of the serve

You can take a look at the serving action of computer tennis games, which are generally good standards! Let's talk about practicing aerial shooting movements.

Throw the ball high, about about the same distance from the first racket.

Observe the other people's serve and learn more from the famous Roddick Isner.

You use the striking point as a clock, brush from seven o'clock to one o'clock, and remember to brush it by all means. That's what my coach taught.

Do the right action repeatedly and keep it a habit.

You can change it, don't rush to serve, the action is done.

Practice the salute a lot, it's very practical.

Most of the time, the serve should be played within 20 seconds of the last score.

Starting in the 2013 season, a new penalty of more than 25 seconds between points will be applied for both ATP Tour and ATP Challenger tournaments, and if a player runs out for the first time, he will receive a warning, and the second and every subsequent time will be counted as a service error (for the serving side) or a direct penalty (for the receiving side). Previously, the penalty for this phenomenon (too long time between points) was only a warning.

From the start of preparation to the serve, 25 seconds, otherwise warning, if you deliberately delay, you may lose points directly.

The direction of <> is opposite to the direction of initial velocity (2) <>

The direction is opposite to the direction of the initial velocity.

Let the direction of the velocity of the tennis ball be positive, then:

The muzzle velocity of a tennis ball <>

**Rear speed <>

1 point) 1) So the momentum change of the tennis ball:

(2 points) So the magnitude of the change in momentum of the tennis ball is <>

The direction is opposite to the direction of the initial velocity. 1 point).

2) <> by the momentum theorem

It can be seen that the average force of the racket on the tennis ball:

(2 points) The average force of the racket on the tennis ball is <>

The direction is opposite to the direction of the initial velocity. 1 point).

This question examines the application of the law of conservation of momentum, the velocity of the tennis ball becomes reversed after being hit by the racket, the direction of the initial velocity is specified as the positive direction, and the change of momentum can be obtained after determining the initial and final state.