The following is an excerpt from the book The Fault Tolerant Forehand, which will be released in early 2021.
The Fundamental Theorem of Tennis is two rules that govern every shot in the game. They are as follows:
1. The racket makes a 90-135 degree angle with the forearm
2. The racket strikes the ball in front of the body (or, in a pinch, in front of the forearm)
Any shot which follows these two rules will work. I should specify that I usually verbalize this rule as “a 90 degree angle” instead of “a 90-135 degree angle”, even though that’s often an exaggeration; many shots in tennis are played with a 135 degree angle, but I find that verbalizing and thinking about it as “90 degrees” produces the best results, since many students’ natural intuition is to play shots with a straight, 180 degree racket/forearm angle, and thinking about “90 degrees” prevents this.
Following these two rules puts the racket in a position to function as a trampoline off of which the ball can easily bounce. The forearm will facilitate velocity transfer back to the ball much better when the racket is perpendicular to it, rather than in line with it. Additionally, control over the racket is far superior in this position. There are many ways to rotate the arm-racket system while maintaining a 90 degree forearm/racket angle, and all of these will produce good shots. Further, there are many axes along which the racket can flick around the hand when cocked at roughly 90 degrees before starting the swing. This is especially necessary for shots performed while on the dead run. Mentally curing your racket to stay at 90 degrees will prevent you from attempting to adjust to balls by moving only the racket head without adjusting the entire arm-racket system; this incorrect, independent racket head movement elongates the angle between the arm and racket and causes you to lose fine control over the racket head’s movements.
As a last point of interest, as noted in the rule, in a pinch it’s not necessary to contact the ball in front of the body as long as the racket still hits the ball in front of the forearm. Think of full stretch volleys out to the side, or shots where the ball has bounced behind the player. In these cases, as long as the player is able to maintain some sort of an angle between the racket and the forearm and get the racket flicking forward by the time it strikes the ball, the ball will usually go in. There are many different ways to flick the racket around the hand. You’ll notice that good players on the full stretch often end up following through awkwardly in front of them, rather than around their body, because they’re focusing on generating any and all forward flick of the racket that they can muster from such a compromised position.
The Fundamental Theorem of Tennis is just one of many principles discussed in The Fault Tolerant Forehand, which will be released in March of 2021. Many pages from the book will be made publicly available completely free as they are completed, so don’t miss out! Great tennis is all about understanding what the game is truly about, and building from there. We don’t start with the joint angles, no “feet here, arms there, elbow does this, wrist does that.” Instead we start with a simple answer to a simple question.
How do I strike the ball to make it consistently do what I want?