early flexion

Pitching with a sway and how it can impact your rotational power.

Swaying is one of the big 12 pitching technical characteristics that OnBASE University have identified. This article will dive into what swaying looks like and what can lead to swaying. All of the identified big 12 does not necessarily equate to poor performance. But when a pitcher has trouble with consistent delivery, understanding how your physical body make-up can give you clues on why you might be swaying during the early part of your pitching sequence.  Improve your pitching rotational power by knowing if you have sway or not with this article.

The good news is that this step-by-step article will help you tease out if you have physical mobility, stability, or pitching technique problems.  

What is the “sway” pitching posture?

Swaying can be seen when you look at the pitcher face-on. As the pitcher raises his front leg (“pivot” to “top of leg lift”), an energy-efficient strategy will have the pitcher’s torso be vertical or leaning forward to the inner knee of his stance leg. A pitcher will sway if they shift behind this imaginary vertical line drawn from their inner stance knee towards their head.  

What does this mean from a physical standpoint?

The goal of the pitching sequence from “pivot” to “top of leg lift” is to prepare and load the body to produce explosive rotational power. The power that needs to be displayed as precise pitching accuracy towards the home plate. The back stance leg sets the tone as two factors: setting up the stability of delivery and transfer the ground reaction force up to the pitching arm. The muscular or dynamic coordination of the entire stance leg, from hip to ankle muscles, will titer the torso to stand erect, swayback, or direct forward towards home plate. Two important muscles that will impact stance leg control are the Gluteus medius and Posterior Tibialis muscle. More to come on this.

You do not want any movement “leaks” during the pitching sequence, as that will result in higher energy use. A pitcher will later be fatigue and this can cost him pitching control in later innings. They will force the throw to make up for this movement leak during the wind-up.  

Before we dive into the checklist that a pitcher needs to assess when there is a swaying phenomenon, it is important to know that joint or soft tissue mobility will limit muscular dynamic performance. Check mobility before you put all of your eggs in your bucket on stabilizing and strengthening. Muscles have fibers that allow it to be elastic and dynamic like a rubber band. A thick and stiff band cannot explode as far as a pliable rubber band.  

Several physical limitations may cause a Sway: 

  • (Stance leg) Hip Internal Rotation Mobility. If you have limited hip internal rotation, your pelvis will be blocked to load efficiently. When you stand on your back leg to wind-up, your trunk rotates away from the hitter. This trunk rotation will result in an indirect internal rotation of the hip of your stance leg (toes pointing towards midline or navel).  

When the body cannot move into the rotation, it will use the other planes of motion to compensate. Thus, the trunk will deviate laterally away from the batter.

OnBASE U’s screen to test: TOE TAP TEST

Corrective exercise =

  • Backside Ankle Mobility. Your heel can shift out (eversion) and inwards (inversion). When the pitcher winds-up, he drives his stance leg heavily into the ground to produce ground reaction force. As the pitcher reaches into a long stride, the heel needs to shift into eversion for ground reaction pushing force transfer. When the stance leg (backside) heel cannot load into eversion due to mobility and joint stiffness, the pitcher cannot leverage the ground reaction force that the legs need to develop stability to rotational power.  

OnBASE U’s screen to test: ANKLE ROCK AND ROLL TEST 

Corrective exercises = Heel to heel slap. Sit down on a chair and cross your pitching stance leg’s heel onto your other knee. Pull your toes and forefoot into dorsiflexion (toes closer towards the shin). Take the heel of your other hand’s palm and with quick and moderate force, tap your palm towards your ankle’s heel 5-8 times. The speed of tapping is more important than force.

  • Limited Spine Disassociation. Imagine a slingshot’s explosive power comes from the “stretch pull-back” loading of the elastic band. You need your upper body to rotate independently from your lower body’ pelvis during the wind-up. The better the pitcher can control this rotational spine disassociation, the better the pitcher can produce the counter-rotation explosion of the ball out of the hands.

There are many reasons for having difficulty disassociating your spine. There are numerous muscles and joints around the spine and pelvis that functions to rotate your spine. Dysfunction to the Abdominal Obliques, ribcage Intercostals muscles, ribs, and/or thoracic spine mobility.


Corrective exercises = Brettzel stretch.  Lie on your side and flex your top hip up past 90 degrees and hold onto it with your bottom hand. Turn your bottom hip outward and try to grab your ankle with your top hand. (Don’t grab onto your foot. If you can’t reach your ankle, loop a towel around your ankle and grasp the ends of the towel.) Once in the position, contract the glutes (butt muscles) in your top leg and contract the quads (thigh muscles) of your bottom leg. Aim to try to bring your top hip down and to straighten your bottom leg all the while resisting with your hands. Hold this contraction for five seconds. Then, relax and immediately rotate your top shoulder toward the floor. Hold this position for five seconds then return to the start position.

  • Limited Lower Body Stability – Power is great only if you can control the power. The ability to laterally stabilize your stance leg during the wind-up to leg lift will help to harness the strength and proper movement control of the lower extremity, gluteal, and other core muscles. 


Corrective exercises = Half-kneeling narrow base exercise.  The test is the actual training. The more practice, the better your testing will be.

  • Front Side Hip Flexion Mobility – The pitcher’s ability to raise the stride leg can directly impact the stance leg’s stability. This impacts the test listed above. As both legs (hips in this case) rely on each other for optimal performance, stability, and force production, a tight stride leg will cause the stance leg to compensate to overcome the tightness.  


Corrective exercises = Supine knee to chest stretch.  Lay on your back and pull the stride leg’s knee to your chest. Inhale and exhale for a count of 10 SLOW breathes. Try to repeat this maneuver but in standing as a progression. Make sure your feet are facing straight ahead.

There you have the full picture of how the “sway” can impact a pitcher’s performance and rotational power production. Test to see if you have any of these common reasons if you notice on the slow-motion video that you have a sway. Perform the corrective exercises for 4-6 weeks for desired changes.  

We specialize in recurrent muscle tightness and the pain the comes with it. Get your expertise second opinion with a click of the orange button below.


Danh Ngo PT, DPT, OCS, SCS

Doctor of Physical Therapy

Board Certified Specialist in Orthopedic and Sports Medicine

Onbase University Certified Pitching Specialist

Certified Advanced Movement Specialist – RockTape

Certified Mobility Specialist – Rocktape

Mind Body Health Results Coach