IRCT2017011426346N2 IRCT 2017-05-02 Research Department of Tehran University of Medical Sciences effect of fatigue on trigger point of upper trapezius muscle Trigger Point (TrP), Upper Trapezius (UT) Effect of fatigue on neck joint position sense, pressure pain threshold and pain intensity in trigger point of upper trapezius muscle 2016-10-22 anticipated 64 Complete https://irct.ir/trial/21849 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment. N/A Neck pain. Intervention 1: Fatigue in control group subjects were asked to perform a dominant shoulder elevation against the force transducer with as much force as possible for at least 10 sec. This procedure was repeated three times with in-between breaks of 20 s. If the highest force was measured in the last MVC contraction, an additional contraction was performed. The maximum number of MVC contractions was limited to three. The highest measured force level was assumed to be the MVC of the trapezius. Again the highest force value was considered to be the MVC. After a break of 5 min, a sustained submaximal contraction of the trapezius was performed. The subjects were asked to sustain a unilateral 80% MVC isometric shoulder elevation until the force gauge monitor showed 50% of MVC in least 3 minutes. Intervention 2: Fatigue in Internationale group subjects were asked to perform a dominant shoulder elevation against the force transducer with as much force as possible for at least 10 sec. This procedure was repeated three times with in-between breaks of 20 s. If the highest force was measured in the last MVC contraction, an additional contraction was performed. The maximum number of MVC contractions was limited to three. The highest measured force level was assumed to be the MVC of the trapezius. Again the highest force value was considered to be the MVC. After a break of 5 min, a sustained submaximal contraction of the trapezius was performed. The subjects were asked to sustain a unilateral 80% MVC isometric shoulder elevation until the force gauge monitor showed 50% of MVC in least 3 minutes.