How/why does an isometric contraction activate an inhibited muscle?
Isometric contractions are targeted at restoring optimal neurological input to the muscle. When a muscle becomes inhibited it loses proper neural input from the nervous system; technically speaking, the ‘gamma input’ [a neural communication to the muscle] becomes inhibited, which is regulated by the ‘muscle spindle’ [a tension regulator]. By isolating the muscle (as best as possible) in a shortened position—contracting it with very little force and for a very short time (6 seconds)—it sends the message to the nervous system “hey remember me?” The goal of these isometric contractions is to get the traumatized muscle to safely move back into a (previous) position of vulnerability. Once in that position a very light contraction (10% of force) is done for 6 seconds and repeated 6 times with a brief rest in between repetitions. The nervous system is repeatedly reminded of this circuit. If done correctly, it will result in the inhibited muscle being activated.
