In my years of experience playing tennis professionally and in teaching the sport to many top juniors, I have noticed a common thread with the majority of errors made in tennis matches. I have experienced many frustrations myself, and I have also watched players I have been working with miss a crucial shot after having drilled the forehand for hours and hours. I know that the forehand down the line has been practiced thousands if not tens of thousands of times, so why did that error occur?
Shot selection is the answer. A high percentage of errors made on the tennis court occur when players are attempting to hit a shot that is simply just not warranted. Players will try to hit a winner down the line when the best shot selection would have been to go back cross-court for that specific shot. You will often hear comments about how players like Federer possess such exceptional shot selection. What does Federer know that average Club players don't know?
Unfortunately, we don't have the luxury of time in the middle of a point to decide exactly which shot will be the best for the moment. We need to train players to think instinctively along the lines of directional change, speed, and ball force, in order for their first shot selection to be one that is aggressive enough to stretch their opponents but not too reckless bringing in unnecessary errors.
For many years tennis players and pros have discussed when to and when not to change the direction of the ball. It is always safer to hit the ball back along the same direction as it came towards the player. A few years ago some research was undertaken on directional change and it found that the top 10 players on the ATP Tour were the players who least changed the direction of the tennis ball during points.
For this reason, I teach my players the relativity theory of how the ball is traveling in relation to their body. This theory covers the angles the ball travels towards us, the speed, height and spin on the ball. Ultimately, because tennis is a reaction sport, the ball dictates how the player must hit it and what shot they should be trying to execute.
If the angle of the ball traveling towards us crosses over us (Outward ball) this ball is to be returned back on the angle the ball came from. When the angle of the ball traveling towards us angles inwards (Inward ball), we are able to either go back on the angle that the ball came or change the direction of the ball with control no matter the incoming speed. This is because of the laws of deflection. These laws and forces are what need to be overcome when trying to change the direction on the outward ball. The required force of the racquet needs to be ten times greater than the force the ball makes when making contact with the racquet.
Research shows that in order for the force of an 11.5 ounce racquet to amount to 10 times greater than the balls force, then the racquet needs to travel almost double the speed of the incoming ball. Therefore if a player wanted to change the direction with control, off an outward ball, they would need to have their racquet travel approximately double ball's speed. Imagine the incoming ball traveling at 40 mile per hour. Then the racquet would need to travel at nearly 80 miles per hour in order for the force generated by the racquet to be sufficient to change the direction with consistency and control. With the racquet traveling at nearly 80 miles per hour, there isn't too much control and without control there is less consistency. In this instance my advice to players is to keep the ball going back in the direction that the ball came from. This will enable the player to hit the stroke with control and consistency, and with a high allowance for an error.
Because of the force that the ball exerts in making contact with the racquet in the above example, changing the direction in this situation is the wrong selection. However, if the ball was slower and traveling at 25 mph, the force of the ball on the racquet can easily be counteracted with a controllable racquet speed and therefore changing the direction of the point would be the correct selection of shots.
The ball speed will set the parameters on how it can be hit. Players like Federer are so focused on the ball and what it is doing in relation to themselves that they are able to select the better option more frequently. Understanding the physics of directional change will help you successfully implement directional changes at the right time!
