You hear it all the time. It comes from amateurs at public courts, who unfortunately may not know any better. But when highly paid television commentators talk about it, I get kind of sick. After all, the ball is only in contact with the strings for 1/1,000th to 3/1,000th of a second. Yes, that’s milliseconds. How fast is a millisecond? To give you a comparison, a regular light bulb cycles at 1/60th of a second. So, a ball is in contact with the strings and leaves the strings at least 20 times faster than the flicker of a light bulb (which the human eye cannot detect). After all, when we look at a light bulb we only see a steady stream of light.
So, considering the brevity of the event we call ball contact, how can a player possibly “roll over” a ball to create topspin? The fact is that they can’t. Three things affect spin and arc (or trajectory).
1) The angle of the incoming ball
2) The angle of the racquet face at contact
3) The path of the racquet face during that brief moment we call contact
As much as I am a fan of many of television’s tennis commentators, I hope at least one of them will read this blog and stop perpetuating mis-information like this that slows down the improvement of many tennis players.
What does create topspin? Take a look at one of the YouTube clips on this webpage to get a good visual reference.