In this text we refer to right-handers, so left handed had to read left instead of right.
Introduction to the technique of forehand topspin
The technique of topspin that underlies the modern competitive tennis: almost all ATP players use it (or try to do so), has, in short, for the forehand, the following characteristics:
● the racket moves with the movement of windshield wiper.
● the racket is always upright and always look to the net, from a few moments before impact until the follow trought.
In order to achieve this you must give up almost all the features of the traditional technique (flat stroke).
See at a glance the points that will be developed in the various pages of the site):
● topspin movement is with the body in front of the net – open stance (at most in semi-open stance); while traditional stroke movement is with the body perpendicular to the net.
The openings may seem similar, because the trunk is approximately perpendicular to the net (and the racket is brought towards the rear fence), but your feet, unlike the traditional position, are parallel (or nearly so) to the net.
● topspin movement is based (mostly) on the rotation of the body, and there is no more linear motion forward traditional stroke (there is no longer a transfer body weight to the front leg).
In the topspin forehand the body actually makes a 180° rotation, even if your legs are in the open stance: in the preparation/opening the chest is facing the right side of the field (apart from the position of the legs, the position of the trunk is here that traditional stroke) while closing the chest is facing the opposite direction.
● topspin is the movement of the body which develops the force that is applied to the racket (the arm is as inert), whereas in the traditional shot his arm (and shoulder) produces much of the force that moves the paddle.
● in the topspin the racket performs a semicircle from right to left (for right handed players) like that of the windscreen wiper, while in traditional hit the racket moves only bottom to top in the direction of the net.
● topspin racket largely peeling ball from bottom to top, while in the traditional stroke it pushes the ball forward.
● in the topspin the grip is (most likely) different from the flat shoot (these are personal choices, but for best results you need to force the handle moving the palm below the grip).
The handle that allows to obtain an excellent topspin is “extreme”, and then it also requires an adjustment of body position to not have your bat to land turned to send the ball into the net.
● in the topspin the wrist does not produce any movement, but it’s relaxed: it is solely the movement of the arm (and, in the best cases, including that of the body) that transmits to the racket the rotation of the windscreen wiper.
See an interesting way to learn how make the ball spin
See a very well page on teaching and training for the topspin forehand https://www.tennisplayer.net/public/classiclessons/chris_lewit/building_the_spanish_forehand_exercises/