Slings are groups of muscles that work together to create movement, resist movement and assist in controlling the movement created by other slings. It is important as fitness professionals to understand how they work so you can assess their function and correct faulty or compensatory movements created by dysfunctional sling activation. We also need to be able to train the sling systems to maximize their potential to create power.
Think of slings as ropes. Each rope runs through the body and creates movement when contracted. These ropes can resist movement when they contract in unison with the sling on the opposite side of the body. Look at the Anterior and Posterior slings below. If you put tension on both slings you will stand tall. If you release the posterior sling and pull on the opposite or anterior sling you would create flexion. This is very basic but you need to understand and picture this before we go into the more complex rotational slings.
The purpose of learning about these slings is to help you analyze movement better. I believe the best way to analyze movement is to look at it like a snapshot or blink of the eye. You first impression of whether it was good or bad form or movement is usually right. Now make the cause and effect of the movement as simple as possible. Which rope or sling would cause that movement? What rope would you pull or release to correct that movement?
The slings that create rotation can be extremely complex. They wrap around the body and can act as rotators to create disassociation, resist rotation and also aid in over all stability when coupled with other slings. You can follow the lines of the slings by following the fascial lines or look at the muscle striations. The can easily be seen on an anatomy chart but can be too complex to visualize when your athlete is in motion.
To simply the function of these slings we are going to look at them as 2 crossing slings on the front of the body and 2 crossing the back.
Now picture these slings as ropes. Anchor the ropes to the pelvis and pull them individually. If you pull the anterior right sling for instance the body would flex and rotate to the left. If you pull the posterior left on its own the body would extend and rotate left. I you pulled both the anterior right and posterior left at the same time with equal force you would rotate to the left without flexion or extension. Now look at a golfer at impact. Can you analyze whether there is too much flexion or extension while rotating?
Training the rotational slings requires you adding load to the movement patterns that the slings create. There are a million different exercises that you can use but encourage you to adhere to my rule of rotation:
You have to earn the right to rotate!
What this rule means is that you have to demonstrate the ability to resist movement using the slings as stabilizers before you can use them as mobilizers. Examples of resisting rotation exercises would be a High Threshold Shoulder Tap from my Online LoadXplode and High Triplexity Programs. Lifting of right hand will cause the body to want to rotate toward the lifted hand. Your posterior right slings will have to fire to hold the body in place and resist rotation.
Once the athlete has earned the right to rotate you can have them rotate. You can challenge the rotational slings as decelerators or work them eccentrically like in the example below. The Contralateral Reaches challenges the posterior right sling (when reaching with the right hand) to control rotation.
Below is a Disassociation Plank. To perform this exercise you set up in a plank, keeping the lower body stable, rotate your shoulders using your posterior right sling and raise your right hand to the sky. Put your hand back on the ground, while keeping the upper body stable; fire your right knee toward the left shoulder using your anterior right sling. This actually simulates a right handed golfer’s loading phase in their backswing followed by their lower body initiating proper sequencing by firing on their downswing.
If you want to continue the discussion, I recorded an episode of the Coach Glass Podcast on this very topic! Enjoy: