A comparison of scapulothoracic muscle electromyographic activity in subjects with and without subacromial impingement syndrome during a functional task.

Shoulder impingement syndrome (SIS) is the common cause of shoulder pain and disability and the individuals suffering from it are usually in different levels of physical activity covering an extensive age range. In spite of limited scientific evidence for an altered motor pattern in the shoulder muscles of patients with SIS, they are frequently referred to physiotherapists in an attempt to optimize coordination and strength of the affected muscles. The aim of this study was to compare scapular muscle activity in a general population of subjects with and without SIS during an arm elevation task executed at different speeds in two load conditions. The study is that of a comparative observational using a simple convenience sampling method, comprising 8 females (31.63 ± 9.39) with SIS and 10 females (29.10 ± 6.57) without SIS, matched in terms of age, body mass index (BMI) and levels of physical activity. The surface EMG (SEMG) of all the trapezius muscles, i.e., -upper fibers (UT), middle fibers (MT), and lower fibers (LT) serratus anterior (SA), and middle deltoid were recorded during shoulder elevation in a scapular plane at three speeds (slow, moderate, and fast) and two load conditions (with and without load). Data were analyzed using independent t-tests and three-factor repeated measures analysis of variance and Bonferroni method for paired comparisons. The EMG tests results in muscle activities revealed no significant differences between the two groups at three speeds, and with and without load. The findings do not support the claim that SIS necessarily accompanies changes in scapula thoracic and glenohumeral muscle activity.

Effects of cyclic static stretch on fatigue recovery of triceps surae in female basketball players.

Static stretch is a safe and feasible method which usually is used before exercise to avoid muscle injury and to improve muscle performance. The purpose of this study was to determine the effects of cyclic static stretch (CSS) on fatigue recovery of triceps surae (TS) in female basketball players. Nine athlete volunteers between 20 and 30 years participated in this study containing two sessions. After warm-up a pressure cuff was fastened above the knee joint and its pressure was increased to 140 mmHg. The subjects were asked to perform one maximum voluntary contraction (MVC) followed by a fatigue test including maximum isometric fatiguing contraction of TS. These steps were similar in both sessions. Then, a two-minute rest was included in the first session while 4 static stretches were performed to TS in the second session. After interventions, one MVC was done and the pressure cuff was released. During these steps, peak torque (PT) and electromyography (EMG) were recorded. The amount of lower leg pain was determined by the visual analogue scale (VAS). The value of PT increased significantly after CSS but its increase was not significant after rest. It seems that the effects of rest and CSS on the EMG parameters, PT and pain are similar.