There are major differences to both of them and are hard to capture with an untrained eye, many inexperienced or experienced tennis coaches also struggle with this all over the world and in Singapore.
When you Snap your wrist during your tennis serve (assuming perfect technique and grip), the racket head will finish with the top leading and the sides of the rackets parallel to each other.
When you Pronate to serve in tennis, the edge of the racket ( assuming correct technique and grip) will lead the swing.
Pronation is the only ‘right way’ to serve in tennis.
For me as a tennis coach from Singapore, I believe that there is only one way to serve in tennis and that is to Pronate during your tennis serve.
Issues with snapping the wrist on the tennis serve. Many tennis students, tennis coaches and tennis players say that using your wrist to dominate the tennis serve will give good feel, directional control and tennis racket head speed. That i feel, is false. And i want to give a few reasons why you should not use your wrist.
By snapping on the tennis serve, your wrist takes the full extent of the force created by your kinetic chain, ( you drive your legs from the ground storing energy, building up to throw you arm)
At that point while your energy is moving from your arm toward the tennis ball, you snap your wrist, that movement stops the kinetic chain at the wrist, making your wrist take the full impact from your stored kinetic energy which means that there will be no energy transfer from the ground to the ball because it stops at the wrist. Which will cause injury.
Next, after u lose all the stored energy at the wrist, you now have to use your wrist and forearm to snap at the ball as fast as you can. Which will also cause injuries because, the tennis racket is heavy, and your wrist and forearms are small muscles and will not be able to constantly handle the weight of throwing your racket. Especially if your racket is 300g or heavier. You will definitely get wrist pains or forearm pains.
Lastly, there is no directional control because in the human body, areas like the wrist have a huge range of motion and that makes your tennis serve inconsistent because you cannot possibly control the minuscule differences in the movement. Even a tiny 0.1cm difference leads to an entirely different contact point.
Also, for shorter players, the snapping makes the ball travel downward at a steeper angle, which makes it hard for you to clear the net especially if you are 1.75m and below.
Pronation is the only way to serve in tennis
Why pronation is the only way to serve in tennis
When you pronate correctly on the tennis serve, you save your arms from major injury because you rotate your rotator cuff muscles while your arm is straight and slightly away from your face/neck.
This will help you to not get your wrist injured, and also to save yourself from shoulder impingement because your shoulder joint is further away from your neck while hitting the ball.
Next, you will be able to get the full force of the ground kinetic chain you have build up with your legs because that is no sudden movement change or chain stoppage.
Finally you will be able to control the tennis serve better because there is no large range of motion from the wrist, the shoulder has a minimum range of movement, just like when you hit your ground strokes, you want the shoulder to do most of the work because the differences in movement is small, thus you will be able to get used to being a certain distance away from the ball all the time, which will get you to be more consistent.
The pronation will also give you a less steep downward angle because it relies solely on the ball toss. If you toss the ball straight up the ball will travel in a straighter path, if you toss the ball infront of you inside the court, the ball will travel a more downward path.
So it is far easier to be consistent and to control the serve.
The biggest factor is the difficulty in learning the pronation for the tennis serve. One has to change their entire mindset because it does not seem possible to do. But with proper practice and determination, anyone can pronate for the tennis serve.
If you want to learn the right way to serve, come have a tennis lesson with us :)