Читать книгу Tennis Method - Defined Timing - Siegfried Rudel - Страница 9

It has already been mentioned that the player's movement is the establishment of a relation between himself and the ball. This relation is established evem before the player touches the ball with the racket face by orienting to the opponent's stroke and the behaviour of the ball during the flight. The better the player adapts his movements to the behaviour of the approaching ball as far ds space and time are concerned, the more exactly ('timed') can the stroke be performed. The demands on the relationship to be described must encompass all space-time relations between player and ball before, during and after hitting the ball. In doing so, the contact movement between racket face and ball is helpful.

Just imagine the following situation: Two players are standing opposite each other, one of them perpendicularly strikes the ball up to the height of his head. It is the other player's task to catch the falling ball with the racket face so that the ball does not hounce.

From this the following movement sequences are developed:

• striking perpendicularly downward when the ball is rising or falling above net height;

• striking perpendicularly upward when the ball is falling for the first time;

• hitting perpendicularly upward after the ball has touched the ground and is rising again (figure 3);

• hitting perpendicularly upward after the ball has touched the ground and is falling for the second time.

Figure 3 : Half-volley - vertical aspect

In order to catch the ball smoothly, the velocity of the movement of the racket face must correspond with the velocity of the ball. If the player right from the time of his partner's stroke tries to follow the vertical movement of the ball with his racket face, the approach to identical height when the ball falls can easily be achieved. In order to perform this movement, the space-time-relation can be determined. In doing so, the 'timing' of the racket face movement represents the performance of the movement of the whole body. This acquired vertical contact behaviour is also used when performing the movement sequences mentioned above:

• When striking downward: in doing so, the racket face first all follows the upward movement of he ball; during the strike it moves downward·. This movement goes hand in hand with an upward-downward movement (smash/service) of the player.

• When striking upward: first of all, the racket face follows the upward movement of the ball, then it moves downwards, and after this, during the strike, upward again. In doing so the racket face causes the player to make a downward-upward movement with a rhythmical change (volley, half-volley, groundstroke).It does not matter how high the hitter strikes the ball, the timespace relations remain constant.·The movement rhythms created for the strokes mentioned above can be transferred to:

• all smashes and services

(hitting zone during the first rise and first fall above net height)

• all volleys (hitting zone during the first fall of the ball)

• all groundstrokes.

(hitting zone during the second fall after bouncing (figure·4).

Movement Rhythms	Strokes	Moment of hitting	Racket face movement (vert.)
1	smash /service	during the 1 rise a. first fall above net height	upward - downward
2	volley	during the first fall	upward - downward - upward
3	half-volley	during the rise after bouncing	upward - downward - upward
4	groundstroke	during the second fall after bouncing	upward - downward - upward

Figure 4: Division of the strokes according to movement rhythms

The cause is the independence of the respective horizontal velocity of the ball. If the players move away from each other, the 'catching movement' must also be adapted to the horizontal movement of the ball, with the time constancy in the vertical relations remaining the same. In doing so, the racket face can 'stick' to the ball within the direct space of movement However, as soon as it leaves this space, the longitudinal axis of the racket which points to the ball, keeps contact by means of the simultaneous drawing' of the flight curve of the ball (figure 5).

Figure 5: Half-volley - 'drawing'

The rhythm which is created by this keeping of contact, as discussed above, makes possible a controlled imparting of impulse at the moment of hitting. Even if the impulse time only lasts part of a second and no conscious movement correction is possible, the form movement of the racket face must correspond with the actual as well as with the required flight curve before as well as after hitting the ball. This is achieved by a 'guiding path' which is as long as possible. At the same time, the centre of the racket face is level with the target direction, the vertical movement regulates the height, and the inclination of the racket face influences the modulation of the ball flight. If, for example, the ball must be hit without spin, the racket face must be perpendicular to the present movement direction of the ball at the moment of hitting. Since, however, the movement of the ball changes during the movement of the racket, the inclination of the racket face must correspond with the flight curve of the ball by a rotation around the longitudinal axis. Thus, the flight curve of the ball is first of all followed and then anticipated by the 'opening' and 'closing' of the racket face.

However, the racket face is no object hanging in mid-air, but the player must set it into a corresponding motion. In doing so, he orientates his movement action (movement of the racket face) to the ball curve, in moving upward and downward to the vertical aspect, in moving to and fro to the horizontal aspect, and in changing the inclination of the racket face to the connection between the vertical and the horizontal aspect of the ball curve.

The transmitting of the ball curve via the movement of the racket face to the player's body is a grasping, a feeling, a simultaneous 'drawing' of with the player perceives of the ball curve with the aim to determine the future movements of the ball in the 'guiding movement'. This succeeds the better, the more exact this unity with the ball, the unit of perception and movement, is achieved.