To Mobilize or to Stabilize, That is the Question...

The mobility vs. stability debate is a classic argument that I have run into in my practice a number of times. Some practitioners come from the camp of "let's release everything" and give out rolling, stretching and smashing exercises until there is nothing left to mash; while others only prescribe stability exercises to strengthen the affected area. Doing only of of these alone will not solve the problem. Both need to be addressed and with proper assessment.

Before delving in, I think its important to define a couple of things:

1. Flexibility: The amount of range that a joint or structure can achieve passively and independent of strength.

2. Mobility: The amount of range that a joint or structure can achieve and actively control.

3. Stability: The amount of resistance that a joint or tissue can withstand.

With these definitions in mind, it is easy to mistake flexibility with mobility. Often, "mobility" drills are prescribed without a stability component, actually just making them flexibility drills. In order to actually achieve mobility, a flexibility drills has to have an activation component to them. 


The brain is incredibly good at protecting our bodies. Tension exists in the system for a reason. If you smash the tension right out of a muscle and take the stability out the system, you must provide the brain with an alternative to stability, or else that structure you just mashed is going to tighten back up with a vengeance. Take "tightness" (I put tightness in quotations because tightness does not indicate strength of the muscle. Just that there is tone) in the pecs as an example. Perhaps the pecs are tight because the opposing muscles (such as middle traps and rhomboids) are not firing. You can stretch and roll the pectorals all day and they might feel a lot looser for a few hours. The problem here is that you haven't taught the brain anything. You took away its strategy for stabilizing a potentially unstable shoulder and it knows no other way to stabilize it and will therefore only tighten the pecs right back up. Adding in a very light and gentle activation to the scapular retractors after releasing the pecs will offer the brain an alternative way to stabilize the shoulder (such as a wall angel or a prone scapular retraction). 

On the flipside, if you only do prone scap retractions and wall angels without any flexibility drills to the pecs, you might not be able to actually target the proper muscles because the brain has the pecs so jacked up that they dominate every movement. This is where a combination of releasing and activating is the key.

Something to keep in mind is that, with a lot of our flexibility and mobility drills, we are not actually changing the physical property of the tissue, we are changing the afferent signal that it is given to the brain from that structure. This allows us to tap into the motor control centre of the brain (the HUB of movement!) and gives us an opportunity to teach it something. A release to a structure should be gentle to decrease afferent signal to the brain. When the afferent signal is decreased, there is about a 5-10 second window where doing an activation to the opposing muscle will increase it's afferent signal to the brain, balancing out the brains awareness of the two muscles and allowing it to use both equally. This pairing is creating motor learning and is actually reprogramming the motor control centre. SO FREAKING COOL!

An amazing tool for determining exactly what needs to be released and what needs to be activated is NeuroKinetic Therapy (NKT). NKT is a manual muscle testing system that assesses for the neural connection that the brain has to a muscle. If this connection is lacking, it allows you to determine exactly which muscle is over working for an inhibited muscle. The treatment as per the NKT protocol, is to release (flexibility drill) the overworking muscle and gently activate (stability drill) the underworking muscle. 

If NKT isn't in your arsenal of assessment tools, a great place to start is functional opposites. If you are releasing a hip flexor, immediately activate a hip extensor; if you are releasing an upper trap, activate a lat afterwards. Can't seem to get a hamstring to fire? Try releasing the quadriceps to see if you get more hams activity. 

Every person and nervous system has a different story. Everyone has had different injuries, different sports, different habits and different experiences. and therefore every nervous system will have different strategies for movement. There are no cookbooks for what to release and what to activate, but combining both in your practice is much more powerful than only mobility or only stability. Remember that things don't get tight just because they feel like it. Usually they are overworking to help a lazy antagonist or to protect a joint that the brain perceives as unstable. Don't take stability out of the system without offering the brain an alternative. 

Danielle Boyd