To Activate or Not Activate: That is the question…
Just because a muscle tests weak does not mean it can, should or needs to be activated.
Muscles become inhibited for many reasons. Perhaps it is being forced into a substitution or compensation pattern because the primary motor pattern is not accessible. Perhaps it is because there is a local inflammatory response (ie injury) near by or within the muscle. Perhaps the muscle is lacking in one or several of its primary tenants, S.E.S. (Skill, Endurance, or Strength). Perhaps the joint(s) that muscle crosses are arthritic, inflamed, damaged, remember that an inflamed joint does not like compression/loading. When a muscle contracts it will increase compression across the joint surfaces. Maybe it is being reciprocally inhibited by it’s antagonist, or does not have appropriate sensory feedback from its mechanoreceptors and is neurologically inhibited. The nervous system is wired with many “faults”, which shut things down. Often times, you need to explore the reason why.
So…What happens if you decide to “activate” the muscle regardless of any of the above, which should have been clearly determined by a clinical examination ?
You very well could be forcing that muscle back on the grid encouraging the muscle to perform in an unsafe or undesirable environment. You may be forcing compressive loading across a joint that is inflamed. You could be forcing compression and shear across a damaged cartilage interface, an osteochondral defect, a ligamentous tear or a combination of the above. You will also be over riding the nervous systems inherent neuro-protective mechanism and by forcing the muscle to once again activate and work in a faulty movement pattern. You very likely are reprogramming an unsafe and potentially damaging motor pattern.
Remember, when you “mess around” and over ride neuro-protective inhibition of a motor pattern you reteach a potentially dangerous sensory response telling the joint that the nervous system has been mistaken, that it is actually safe to place load and shear across the joint when in fact it is dangerous. Protective reflexes are there for a reason, to protect you!
We have seen the results of well intentioned or sometimes untrained individuals implementing activation into their clinical practices, coaching, or training. Without a sound clinical examination to determine the reason for muscle inhibition one is taking a whole pile of warning signs and throwing them to the wind. Remember, if you force a muscle back into activation despite all of the warning signs and reasons for inhibition, you will get a temporarily stronger muscle. This is not necessarily success.
In fact, what you have done, is enabled your client the ability to once again impart load and shear across a joint(s) and motor chain that was getting clear central nervous system signals to avoid the loading response. You are essentially forcing a compensation pattern and we all know where that leads to.
As clinicians, we take an oath that states: “Primo Non Nocere”, which means “first, do not injure”. Know what you are doing. If you don’t, then get the training or don’t do it.
The Gait Guys. Were are here to help. We are watching. Do us proud and do the right thing.