Rotational Stability of the Trunk

Rotational Stability of the Trunk

 

When training your trunk (or core) for stability, resisting rotational forces is one complex and important aspect.  Many of the single arm activities that we do, such as the one arm kettlebell deadlift, apply a weight to one side of our body.  This asymmetrical load applies a force on our trunk, which causes it to rotate to one side (our body gives in to the weight).  To stabilize our trunk, we must fight this rotation, and remain "squared off." 

In this picture, the kettlebell in the right hand creates a trunk rotation to the left.  He must stabilize in order to keep his hips and shoulders squared off with a target in front of him

 

There are many beneficial trunk stabilization exercises.  Some are basic, while others are more complex.  Unfortunately, I have seen people in the gym performing most of them with poor technique.  Many people are in a hurry to progress themselves to the more complicated techniques before they really should.  This post will discuss some of the more popular basic trunk stability exercises, proper technique and common errors that I see each day.  It is your job as a trainer to assess your client's abilities in order to progress them properly and avoid injury. 

 

First is the Low Plank and the High Plank.  These are not focused on rotational stability but are more introductory.

Low Plank: Correct - Goal is high reps, holding each one for 5-7sec

High Plank: Correct

 

Low Plank - Incorrect:  This is not acceptable, as you can notice the hyperextension in my lower back and the protruding scapulae.  I am not maintaining stability

  Once you perfect the low and high plank, you may progress to the rotational stability exercise called the High Plank Elbow or Shoulder Tap. 

Wide Base Elbow Tap Start Position

Wide Base Elbow Tap Finish Position: Notice my hips remain "squared off" with the ground

Incorrect Wide Base Elbow Tap: I lost my rotational stability and begin turning my trunk

Progress the above rotational stabilization exercise by modifying the base of support:

Narrow Base Elbow Tap: Start Position and more aggressive due to modified base of support

 

Correct Narrow Base Elbow Tap



Incorrect Narrow Base Elbow Tap: Again notice my rising left hip - If your client is compensating like this even following your verbal and manual corrective cues, they are not ready for this yet

These are just a few of the progressions you can perform when training trunk stability.  Stay tuned for the next post which will discuss other beneficial techniques