The Golgi tendon organ is located at the junction between tendon and muscle. It consists of a group of collagen fibers, which is surrounded by a thin sheath of connective tissue and is innervated by a myelinated nerve fiber. The nerve fiber loses its myelin sheath after passing through the connective tissue capsule and divides into a number of branches that coil around the collagen fibers. The loosely arranged collagen fibers are thought to tighten upon tension and thus exert pressure onto the nerve endings. The resulting impulse is transmitted by the nerve fiber via the posterior root to the spinal cord. Here, the Golgi tendon organ has an inhibitory effect on the motor neurons, thus preventing the muscle from excessive stretching or contraction.