The patient gives the therapist two signals: firstly, at the onset of fatigue and again when a rest is required. The therapist registers the time from the start of the test until each of the two signals. At the same time the therapist observes any increased tone in the global muscles of the patient, and the ability of the patient to maintain the desired position. Any changes from the starting position are noted. If fatigue occurs in less than two minutes, there may be impaired function of the deep stabilizing muscles. Testing of “holding time”for the cervical spine and the lumbar spine is normally performed before Weak Link testing is carried out.