In the world of rehab, fitness, health, and wellness the words “mobility" and “stability" are tossed around like salads at Tender Greens. The challenge is that these catch words are used in many different contexts and are commonly misunderstood.
Here is the Merriam-Webster definition of mobility and stability:
Mobility – the ability to move or be moved freely and easily
Stability – the quality, state, or degree of being stable, such as:
The strength to stand or endure: FIRMNESS
The property of a body that causes it when disturbed from a condition of equilibrium or steady motion to develop forces or moments that restore the original condition
Resistance to chemical change or to physical disintegration
Basically, mobility means to move. Stability means to be still, resist movement, hold firm, etc. That makes sense. Now think about yourself balancing on one leg. What is being stable and what is being mobile? It takes mobility for someone to even pick their own leg off the ground. It takes stability of the spine, and the opposite foot, ankle, and hip, to balance on one leg. So far, the definitions we’ve been given are holding up (pun intended). Now think of walking. We are balancing on one leg the moment our trailing leg pushes off the floor. However, while walking, our balancing leg is moving from a flexed to extended position. More simply put, our hips go from slightly bent to straight while walking. So, is the balancing leg in this scenario mobile or stable? The point of this question is to show that most of the time we have a combination of mobility and stability happening at each and every joint in the entire body. In fact, this combination is critical.
The joint-by-joint approach pioneered by Gray Cook and Mike Boyle really helped to catapult this perspective. However, I don’t think it’s fair to say that any particular joint in the body should be categorized as primarily a mobile or stable joint. It’s always about the context of the movement and what is being accomplished. It is important to remember that mobility is the precursor to stability, and that mobility must be restored before stability can be. This can seem confusing at first, so we as coaches, movement specialists, and therapists need to be specific about the context in which we are applying principles of stability and mobility in order to accomplish specific goals.
Whether it is a therapeutic intervention, a rehabilitative movement, or an exercise intended to improve performance, we can be smarter in the way that we puruse mobility vs. stability. Take crawling as an example. Crawling could be used for spinal stability, hip stability, hip mobility, shoulder stability, shoulder mobility, wrist mobility, wrist stability, etc. Instead of having clients perform crawling because of how versatile it is, let’s understand the exact intention of the movement for our clients’ needs. Maybe a client has low back pain. We’ve identified that they need better intra-abdominal pressure and spinal stability. Great. We’ve hypothetically cleared all the other joints so we know they can handle being in a quadruped position. Awesome. Let’s have the client go on all fours, balance a water bottle on their low back, and raise their opposite hand/knee off the ground to mimic crawling without spilling the water bottle. The client still needs to focus on keeping intra-abdominal pressure with proper breathing. As long as the bottle doesn’t fall, the spine is stable . Boom, spinal stability accomplished via a crawling variation and our intention is a bulls-eye for their needs. Plus, the client still receives all the other joint mobility/stability benefits. The movement can be progressed and the client can improve tremendously faster.
Mobility and stability are yin and yang. Can we be more specific with how we target and improve both, depending on the specific needs of each individual? These decisions can only be made after enough information has been collected via assessment. If you’re looking for help on that path please let me know!