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The purpose of this study was to describe the activity of eight shoulder muscles during the windmill fast-pitch softball throw. Ten collegiate female pitchers were analyzed with intramuscular electromyography, high-speed cinematography, and motion analysis. The supraspinatus muscle fired maximally during arm elevation from the 6 to 3 o'clock position phase, centralizing the humeral head within the glenoid. The posterior deltoid and teres minor muscles acted maximally from the 3 to 12 o'clock position phase to continue arm elevation and externally rotate the humerus. The pectoralis major muscle accelerated the arm from the 12 o'clock position to ball release phase. The serratus anterior muscle characteristically acted to position the scapula for optimal glenohumeral congruency, and the subscapularis muscle functioned as an internal rotator and to protect the anterior capsule. Although the windmill softball pitch is overtly different from the baseball pitch, several surprising similarities were revealed. The serratus anterior and pectoralis major muscles work in synchrony and seem to have similar functions in both pitches. Although the infraspinatus and teres minor muscles are both posterior cuff muscles, they are characteristically uncoupled during the 6 to 3 o'clock position phase, with the infraspinatus muscle acting more independently below 90 degrees. Subscapularis muscle activity seems important in dynamic anterior glenohumeral stabilization and as an internal rotator in both the baseball and softball throws.

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ObjectiveTo update evidence on the effects of breathing exercises (BEs) on ventilation, exercise capacity, dyspnea, and quality of life (QoL) in chronic obstructive pulmonary disease (COPD) patients.MethodsRandomized controlled trials investigating the effects of BEs in COPD patients published through May 2018, were retrieved from five electronic databases (MEDLINE, CINAHL, Cochrane, Scopus, and ScienceDirect). Risk of bias and quality of evidence were assessed, using Cochrane Collaboration’s tool, and the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach, respectively.ResultsNineteen studies (n=745), were included. Quality of evidence, was low to moderate. When compared to the control groups, respiratory rate significantly (p≤0.001) improved in the pursed-lip breathing (PLB), ventilatory feedback (VF) plus exercise, diaphragmatic breathing exercise (DBE), and combined BEs. Additionally, PLB significantly improved tidal volume (p<0.001), inspiratory time (p=0.007), and total respiratory time (p<0.001). VF plus exercise significantly improved inspiratory capacity (p<0.001), and singing significantly improved the physical component of QoL, than did the control groups (p<0.001). All BEs did not significantly improve dyspnea, compared to the controls (p>0.05).ConclusionPLB, VF plus exercise, DBE, combined BEs, and singing could be used to improve ventilation and QoL. Based on low to moderate quality of evidence, use of these BEs to improve ventilation and QoL in COPD patients is conditional (Registration No. CRD42018102995).