Who has the stronger propulsion in freestyle—shoulder-driven or hip-driven? Don’t forget to maintain your core stability during either technique.

•5 min read
Who has the stronger propulsion in freestyle—shoulder-driven or hip-driven? Don’t forget to maintain your core stability during either technique.
When swimming freestyle, the body rotates side to side while alternating arm strokes and kicking motions on each side. Beginners often focus solely on their arm movements and kicks as soon as they enter the water, paying little attention to engaging their core muscles. As a result, their bodies tend to feel loose and lack proper alignment. When they exert force during the stroke, this can easily lead to an undulating, snake-like swimming motion.
Some highly perceptive swimmers will realize that the distortion in their swimming path is caused by the arm stroke "squeezing" their body. As a result, they proactively rotate their bodies laterally—shifting sideways before the squeezing force reaches their core—and smoothly guide the water being pushed inward toward the rear. This approach is indeed correct, but it requires mastering a few key techniques.

1. Shoulder-hip synchronization issues during body rotation

When turning your body to the side, your shoulders and hips should move in sync, though their range of motion doesn’t have to match exactly. As a beginner, if your core isn’t engaged tightly enough—simply put, if you’re not drawing your belly button toward your spine and cinching your waist—the shoulder-to-hip rotation may become uneven. And when there’s an inconsistency between how much your shoulders and hips rotate, it typically indicates twisting at the waist. If your core lacks sufficient strength during this twist, your body is likely to feel unstable and loose, leading to disjointed movements like inconsistent arm strokes and flutter kicks—preventing you from generating unified, powerful propulsion through the water.

Therefore, whether the shoulders and hips maintain a consistent range of lateral rotation should be determined based on your core strength. If your core is stronger, you can afford a greater difference in the amplitude of shoulder and hip rotation—meaning you can twist your waist more significantly without compromising your body’s alignment. Conversely, if your core is weaker, it’s best to keep the shoulder-to-hip rotation as minimal as possible, preventing excessive waist twisting that might otherwise make it difficult to maintain proper posture.

2. How is the range of shoulder-hip lateral rotation defined?

The maximum range of shoulder rotation should be limited by ensuring the elbow does not extend past the back. In other words, shoulder rotation is designed to allow the elbow to naturally and comfortably push the water backward. Importantly, during this motion, the elbow must never cross over the back. If you feel tension or strain in the shoulder joint or upper back while pushing the water, it’s a sign that either your elbow is positioned too far back—or that your shoulder rotation isn’t sufficient.

The maximum hip rotation should be limited to the point where the hips don’t lose contact with the body due to gravity. This might sound tricky to grasp—just imagine performing a plank, leaning your body sideways. If you tilt too far, your hips will no longer have support underneath, making it incredibly difficult to return to your original position. At that point, you’ll either end up rolling completely onto your side or simply collapsing forward at the waist. Similarly, in swimming, excessive hip rotation can lead to one of two problems: either it becomes painfully challenging to initiate the next turn toward the opposite side, or your lower back starts to feel unstable during the movement. As a result, your upper and lower body can no longer stay aligned and rigid as a single unit. Even if your core strength is strong enough to maintain that rigidity temporarily, it’ll still disrupt your swimming rhythm—and worse, it could waste valuable energy by directing effort into unnecessary movements rather than propelling you forward efficiently.

3. The Support Point for Body Rotation
When it comes to body rotation, there’s inevitably a certain range—rotate too much, and you end up doing the side stroke; rotate even more, and it turns into the backstroke. In freestyle swimming, body rotation primarily depends on the coordinated movement of the shoulders and hips, since the shoulders serve as the connection between the arms and the torso, while the hips link the legs to the body. These two areas act as crucial support points after the body initiates its rotational motion. However, for the shoulders and hips to effectively function as stabilizing anchors, core strength must be engaged. If core strength is insufficient, the upper and lower body tend to move independently: the forward-reaching arm may take over as the upper-body support point, while the hips, deprived of that vital core connection, will inevitably sink further—and this can lead to the frustrating issue of "dragging your legs" while swimming.
Additionally, some swimmers notice that when they turn their bodies to the side during the stroke, the palm of their leading arm—which normally faces downward into the water—unconsciously flips upright, adopting a hand-position that resembles slicing through the water. At this moment, if their core strength isn’t strong enough, even a slight loss of control over the hip’s rotational movement can make it difficult to return to the original flat, prone position, increasing the likelihood of tipping onto their side instead.

Share this article

Related Articles