The topics of mobility and stability are widely discussed within the health and fitness world. Contrasting opinions rage to the cost and benefits of not only traditional methodologies, but to the validity of many of our new-age approaches to movement development.
With any discussion however, the fundamental starting point has to be the definition of terms. Therefore what do we mean by the terms mobility and stability?
If we choose to follow the neurodevelopmental perspective, early infancy development between 0-14 months, a key pillar of the IFT training methodology, mobility must be considered first. We are born with near limitless mobility and gain stability as we grow. This initially therefore is a discussion of joints, their capsular integrity and the capacity to enable and control movement, the “hinges on the door” if you will.
Take a watch of Physical Therapist and FMS Co-founder Gray Cook discussing the premise of “mobility first” here.
As we outlined in our introduction to the Joint-byJoint approach in Part One, the body will follow the path of least resistance to accomplish movement based on its basic survival instinct to meet task demands.
Mobile joints can therefore become increasingly stable when full ROM is not maintained and explored often. In turn, stable joints have the capacity to cease intended function and become increasingly mobile when required to provide solutions for activity where a joint no longer meets its primary role of mobility.
If we review our example from Part One of the knee joint, a stable joint must still maintain its normal range of motion in addition to its primary function in stabilising for unrestricted pain-free motion to occur, mobile joints must obey a similar construct. Joints could therefore be considered to have both a primary and secondary function when looked at in three planes of motion.
Interestingly however, renowned Physical Therapist Shirley Sahrmann often notes that “the real problems lie in what moves too much”.
From a practical standpoint, this is easy to appreciate within professions and practices such as Yoga, Dance and Gymnastics, in which the requirement for high level performance is often to obtain extremes in both muscular flexibility and joint mobility to achieve ever more complex positions and patterns of movement.
I’ve been fortunate enough within my own experiences to spend time with individuals immersed in the traditional movement practice of Yoga. Teachers and students alike, some of which enlighten others through the more holistic path, and others that teach from the more strength-orientated, hand-balancing and Gymnastic approach. Yet one thing remains throughout those within the practices, a underpinning display of exceptional muscular flexibility and joint mobility.
Clearly across these disciplines of Gymnastics, Dance and Yoga, a core skill set is shared. Of which a movement such as the Front Splits is a clear recognisable example, an impressive feat that requires dedication and long-term commitment to enable full execution.
In our Front Splits example, when we consider the normal ROM values at the hip joint, approximately 110-130 degrees of flexion, 10-15 degrees of extension, to perform the Front Splits we would need to far exceed this hip extension range to achieve the 180 degree position required.
To achieve this skill we would therefore have to create some level of pathology, “structural and functional deviations from normal”, in hamstring length (flexibility) on the lead leg, as well as creating laxity as the anterior hip capsule (mobility) in the trail leg, as we push the joint and surrounding tissue beyond its structural integrity to obtain the required leg separation needed to perform this movement.
Though clearly obeying the requirement for mobility at a mobile joint, this example fails to maintain a principle requirement of the surrounding tissues, the hamstring muscle group and anterior hip capsule functioning to provide stability to the pelvis. We’ve lost basic function in search of another more extreme, we no longer have the stability we need.
As discussed during Part One, when a mobile joint becomes stable, we see degenerative changes and poor recovery as we’re forced to slow down, our bodies fighting against the daily tasks we ask of it. Equally when a stable joint becomes excessively mobile we see movement dysfunction, herniations, dislocations and subluxations, positional faults and muscle strains.
It is through our own training decisions and choices however that we compound both issues further through our search for extremes. We create our own pathology, resulting in both acute and chronic issues due to the neurological weakness we create in search of both mobility and flexibility.
Mobility at its extremes effect the capacity for stable joints to remain stable by mobile joints become too mobile at the expense of capsular integrity. The impact of widespread excessive mobility on performance is why we develop the stabilisation techniques through the neurodevelopmental perspective so early on in childhood, we need stability to function as adults in the environment we live in.
Yet stability built upon stability comes with its own issues and dysfunctions, as we shall discover in Part Three.