Reciprocal Inhibition

Something that would be good for you to understand for a better idea of what your spasticity is.
http://www.physiobob.com/forum/neuro-physiotherapy/1040-neuro-inhibitory-facillatory-technique.html#post3785

Reciprocal inhibition is the term used to describe a muscle's automatic response to the contraction of its opposite. When the Muscle Control Center (MCC) requests a muscle to contract, that muscle is facilitated, and the opposite, or reciprocal, muscle is required to relax, or become inhibited. The smooth facilitation of the contracting muscle depends upon the smooth release of its functional opposite. Though this is how we tend to explain this we should note that the decerebrate posture is one of flexion or rigidity. Therefore a flaccid arm is really an arm with a lot of input from the brain to relax the flexor tendency. To move say the biceps to flex the elbow would therefore to reduce that dampening on the biceps, whilst perhaps at the same time maybe even increasing it's "relaxation" of the triceps (or not as I am not sure on the reseach here). This concept makes working with head injury and stroke most interesting in deed.

Reciprocal inhibition is a built-in, automatic neurological function, designed to provide for optimum joint function and longevity. It is a fundamental function in proper body movement.

When all the neurological connections between the MCC and muscle are clear, the muscle will be able to respond smoothly and easily to the MCC's signals to work or relax. If one muscle becomes permanently facilitated, as in a cramp, spasm, or chronic tension, the opposite becomes correspondingly inhibited. This disables normal joint function, and results in stress that can lead to deterioration of the muscle, tendon, and joint tissues. In this case, if the client has spasms in their biceps and you test the triceps, you will find it weak.


Another simple example:

To get an idea of reciprocal inhibition in action, hold a heavy book in one hand, palm up. With your other hand feel the front of your upper arm. It's contracted and hard. Then, feel the back of your upper arm. It's relaxed, and flaccid. Include this as a flexibility technique to improve your active and PNF stretching.

Thanks to the Physiobob PT forum.