The “C” swing path on the forehand does exist, but I’m not a fan of its current mainstream classification as a first principle of the forehand, because it isn’t one. The shape and manner of the “C”’s execution changes a lot from shot to shot, because, similar to other derivative aspects of the swing (like the volitional movement of the arm or the follow-through) the specific “C” motion used on a particular shot is dynamically chosen, often subconsciously.
The “C” shape itself is not a biomechanical underpinning of the swing. It’s just created by coincidence in order to serve other, more fundamental goals. On the forehand, the two primary goals are to create up-and-through contact, and to do so by accelerating the racket by rotating the strong muscles of the hips and abdomen. The resulting various “C” like swings are merely a way to naturally accomplish those goals.
I see two issues in coach-player communication, which are common across tennis coaching, that manifest when the “C” swing is coached.
It’s Actually a Warped “C”
The first issue is that a player interprets what the coach tells them to do as being part of the “backswing,” even though it isn’t. With the “C,” some players do not realize that much of the downward part of the C actually occurs during the forward swing. This part is quite abbreviated in its depth; while it happens, the racket is primarily moving forward, not down.
This misunderstanding almost can’t even be called a misunderstanding, because the student is trying their best to create a “C” like they’ve been told. As they try to create the “C,” they’re unaware that the actual swing isn’t exactly a “C,” but rather a modified, warped version of that shape. It’s closer to something like the Nike whoosh, not symmetrical in top and bottom at all.
It’s Not Just a Hand Motion
Second, a player doesn’t always realize which muscles drive a motion their coach is telling them to emulate. With the “C,” this misunderstanding results in a player moving their hand around directly, primarily using the arm and chest, rather than moving it using the muscles of the core.
While the “C” motion does exist (roughly speaking), the “C” is not a motion created primarily by moving the hand around with the arm and chest muscles.
- The initial backward motion of the hand is entirely due to the core rotating away from the target.
- The remaining backward motion is elbow extension; it is not due to pulling the hand back behind the chest.
- The hand is then lowered, and this lowering involves the legs and torso, not merely bringing the arm closer to the body.
- Any remaining downward action takes place during the forward swing, and it’s mostly a passive effect of not resisting gravity. The hand isn’t actively pushed down by the player.
The Underhand Pendulum Swing
Beginners, especially young children, who are taught the “C” as a first principle, often start driving the ball with the wrong force generator. They pull the racket back high, then use gravity to let it fall down and forward like a pendulum. It hits the bottom of the pendulum motion, then bounces back up and hits through the ball.
These beginners initially coached on the “C” end up with a purely arm driven swing, during which they remain sideways, never unwinding their hips and abs. This robs them of the most efficient, effective engine available to them on the forehand, and develops in them a proprioceptive misunderstanding of how racket head speed is generated.
This gravity pendulum effect is a very small effect when it comes to generating force in the modern forehand. Nearly all the force is generated from forward leg drive and hip and abdominal rotation, not the gravitational pendulum.
Therefore, despite the fact that a modified “C” swing path does exist, coaching to that effect doesn’t appear to drive the typical beginner’s natural sense of proprioception to the right place. When they try to orient their body to “perform a C,” they end up accidentally teaching themselves that the forehand is a gravity driven pendulum, rather than a forward twisting motion.
The “C” Can Prevent Jerkiness
Before we move onto what I believe to be a superior way to understand the forehand, I’d like to give the “C” shape some credit. The most comfortable way to allow the racket to flick out to the ball, and then up and through it, is in fact to allow gravity to pull the hand down slightly as it begins to move. The “C” definitely implies that such a downward motion exists.
Without allowing the racket to initially travel down during the forward swing, the motion is far less comfortable, especially on the elbow. If you fully stop the hand after preparation, and then you jerk it only up and forwards from there, actively preventing gravity from pulling it down, the core’s rotational energy won’t be transferred to the arm/racket/hand system as losslessly. The hand absorbs the core’s rotational energy most efficiently when allowed to follow its natural shallow down-then-back-up pattern.
The Two Part Forehand Paradigm
I like to think of the forehand swing as two steps, rather than one:
- Forward swing
The preparation phase ends with the player preparing their hand for the forward explosion. This typically involves lowering it to a height from which it can easily flick up and through the ball. As the “C” correctly asserts, the most comfortable way to fling your hand forward typically involves the hand being allowed to move down first. As a player practices, they’ll gain an (often subconsciously) understanding of to what degree that downward motion happens on each shot, and they’ll learn to lower their hand appropriately during preparation to account for that.
After preparation and before the forward swing exists a waiting period. The waiting period is critical to success in the absence of rhythm. To be able to consistently time balls of various speeds and spins effectively, forehand preparation should be completed as early as possible once the oncoming ball’s trajectory is discovered. This early preparation allows for maximum improvisational freedom with respect to the forward swing itself, because the body has a large window during which it’s fully ready to swing, and the swing can be initiated at any point in that window.
This waiting period can be implemented as a completely static position, but it’s more effective to slow down or speed up the lowering the hand phase in order to time the incoming ball. When preparation is done very early, the hand should be very slowly lowered into position, and similarly, when preparation is done very late, the hand should be quickly thrown down into position and then immediately yanked forward by the core’s rotation from there.
Instead of Thinking About a “C”…
For the top half of the C, just think about regular forehand preparation. Turn away from the ball, and once you do, lower your hand into position. Lower your hand quickly, if you’re pressed for time, or slowly, while you wait for the ball, if you’ve prepared very early.
For the bottom half of the C, don’t think about the racket path at all. Visualize the kind of contact you want to make with the ball, relax your hand and arm, and then drive the hand/arm/racket system forward by twisting your core.
Find an arm path that’s comfortable for you, for which you can feel the efficient transfer of force from your explosive turn into your racket. Allowing your hand to dip somewhat and then bounce back up will feel most fluid, but you’ll need to find the exact manner in which you do so via experimentation. If you force your hand down and back up, the swing won’t work.
Try to figure out what your hand wants to do as you drive it forward with your hips and abs. If something hurts, don’t do it, and if feels good, keep doing it.
The “C” shape is merely a rough visual explanation of what the hand happens to do during the swing, rather than something the hand tries to do. As the hips and abs drive the hand forward, the hand is allowed to fall down a bit before flying back up through contact.
The primary goal of the forward swing is not to create that lower “C” path. The goal is to create explosive up-and-through contact with the ball. Allowing the racket to fall and then spring back up is often the best way to transfer the force from the core’s rotation into that up-and-through contact, but, again, that down-then-back-up motion occurs in service to the rest of the stroke, rather than constitutes its engine itself.