One of the biggest challenges clinicians face during patient care is to determine if a particular tissue needs to be stretched (i.e. a mobility issue) or strengthened (i.e. a stability issue). Mobility may be defined as the ability of the patient to produce the desired movement where stability may be defined as the ability for the patient to resist an undesired movement. Mike Boyle and Gray Cook have developed the “joint by joint approach” and have determined that each joint requires either additional mobility or additional stability to allow for normal function.

The loss of mobility at a joint located above or below a joint that requires stability will result in pain and instability in that less mobile joint. As a joint that emphasizes mobility becomes immobile, the typically stable joint is now required to compensate and therefore becomes less stable and subsequently painful. Examples include: a loss of ankle mobility results in knee pain; a loss hip mobility results in low back pain: a loss thoracic mobility results in neck, shoulder, or low back pain.

The loss of stability may cause muscles associated with that joint to become “overactive” in order to attempt to protect that stable joint. There are many patients who present with what are assumed to be tight hamstrings and regardless how often they stretch, they return to the clinic with tight hamstrings. It could be conceived that this patient could very well be utilizing their hamstrings to compensate for a lack of core stability. In this example, a suitable way to determine if there is a stability issue vs. a mobility issue is by having the patient stand up and while maintaining a straight knee posture while having them attempt to touch their toes. If the patient cannot touch their toes it is either due to tight hamstrings or an inhibited core. Other concerns are certainly possible (i.e. tight calf, tight erectors etc.) but for this example let’s keep it simple. Next have the patient long sit on the treatment plinth and have them once again attempt to touch their toes. The long sit position eliminates the need to stabilize and thus, if they can touch their toes in this position it is determined that the patient has a stability and not a mobility issue. To further test this hypothesis have the patient attempt to touch their toes in standing but this time, have them squeeze a pillow or towel roll between their upper thighs as they touch their toes. If they are able to touch their toes in may be due to the stability provided (i.e. squeeze a pillow) as they are no longer utilizing their hamstrings in the role of a stabilizer. Therefore a stability concern is now confirmed. The patient treatment should therefore be targeted at attaining enhanced core stability rather than the dependence of the hamstrings to control motion.

Attempting to reinstall mobility without addressing stability elsewhere will not last and stability efforts without addressing mobility will result in continued dysfunction. It is important to remember the body’s requirement of a favorable balance between stability and mobility for optimal patient function. The next patient evaluated with a joint or muscle tightness (restrictions) ask yourself is that tissue the cause or the effect (stability vs. mobility) of the patients problem and treat the appropriate tissue to attain long lasting results.

1. Boyle, Michael, Mark Verstegen, and Alwyn Cosgrove. Advanced in Functional Training: Training Techniques for Coaches, Personal Trainers and Athletes. Santa Cruz, CA: On Target Publications, 2010. Print.