Hitting isn’t a once in a while thing, it’s not an occasional thing, or every now and again thing. It requires daily practice with hundreds, if not thousands of swings weekly in the cage or during BP before you even get into an in-game situation. Constant practice is required to perform at high levels and continue to develop as a player. Constant repetition, while necessary, may expose us for greater likelihood for injury or pain when swinging. As is the case with many overuse injuries, we may begin to develop compensations due to muscle imbalances, fatigue or a variety of other factors.
One of the most common overuse injuries in hitters is lower back pain. High torsional and rotational forces that occurs with max effort swings makes it easy to see how any compensations could expose themselves overtime. During the swing, compressive forces on the spine is over 6x your body weight! While the lower back is often the area that the player experiences the pain, it typically is not the area that is causing the pain. There are many different diagnosis that can be attributed to low back pain, but that’s not what we are going to discuss today. Today we want to look at three areas to evaluate, assess, and improve to decrease the likelihood of low back pain with hitting. Those three areas are back hip extension, lead hip internal rotation, and thoracic (mid spine) rotation. We want to look at these three areas because of their proximity to the lumbar spine and because of the importance of these motions to the hitting cycle.
Hip extension is the motion of actively being able to move your thigh backwards past the midpoint of your trunk without arching of your lower back. Without the ability to move your leg back you may experience increased compressive forces on your spine due to the compensation of your lower back having to make up for the range that is not provided by your hip. Here is a simple test you can perform to see if you have full active hip extension. While lying flat on your back with your knees bent, bring one knee to your chest, with the other leg push your foot into the ground and form a “bridge” with your glute. Can you bring your hip fully into the air or is there a limitation or restriction? This would identify decreased active hip extension. Here is a picture to show you what the test should look like.
During this test, you’re looking for a straight line from your upper body or shoulders through the knee.
Lead Hip internal rotation is the ability for your pelvis to be able to fully rotate on your post leg in your swing. So, for a right-handed hitter, this will be looking at your left leg. As your pelvis rotates forward during the swing it requires significant amount of mobility and stability for proper transfer of forces from the ground and your lower half to your core. Inadequate hip internal rotation mobility will lead to early decrease in pelvic rotation which will in consequence require the lower back to make up that extra motion. Here is a quick screen you can use to evaluate active hip internal rotation. To begin, squeeze the foam roller (or any other object) between your knees, maintain that pressure and raise the outside of your heel towards the ceiling.
In this test, you’re looking for at least 45 degrees of hip internal rotation mobility. This can be measured a variety of ways from sitting to lying on your back but what’s most important is that there are no compensations from the pelvis or spine and that the person performing the test is able to control the motion.
Thoracic rotation is the ability for your mid to upper spine to do most of the rotating, as it is supposed to. To put it in perspective, the thoracic spine is supposed to rotate 40 degrees in each direction with the lumbar or lower spine rotating no more that 12 degrees in each direction. If the thoracic spine is unable to reach at least that 40 degrees the lumbar spine will have to make up for it, which will potentially leave you at risk for developing pain in that area. There are plenty of test we can use to look at thoracic rotation but my favorite is to begin in a kneeling position with your glutes rested on your heels, while in that position bring both forearms to the surface you are kneeling on. Next keep on forearm on the ground and place the opposite hand behind your head, begin to rotate towards the ceiling. Here is a picture of this thoracic rotation test.
In this test, you’re looking to be able to rotate to more than 50 degrees from the parallel plane.
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(Inside of Fitness by Erica)
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