Assisting your client with a concentric contraction of an antagonist to trigger the CNS to send a message to relax the agonist is a neural phenomenon called _______________. reciprocal inhibition Reciprocal inhibition is used to relax a muscle on one side of a joint by contracting the muscle on the other side of the joint. This is used to assist the reduction of a muscular tonicity. Caution should be used to prevent a simultaneous contraction which could result in a cramp or muscle tear.