abstract: Individuals fluent in sign language who have at least one deaf parent are considered native signers while those with non-signing, hearing parents are non-native signers. Musculoskeletal pain from repetitive motion is more common from non-natives than natives. The goal of this study was twofold: 1) to examine differences in upper extremity (UE) biomechanical measures between natives and non-natives and 2) upon creating a composite measure of injury-risk unique to signers, to compare differences in scores between natives and non-natives. Non-natives were hypothesized to have less favorable biomechanical measures and composite injury-risk scores compared to natives. Dynamometry was used for measurement of strength, electromyography for ‘micro’ rest breaks and muscle tension, optical motion capture for ballistic signing, non-neutral joint angle and work envelope, a numeric pain rating scale for pain, and the modified Strain Index (SI) as a composite measure of injury-risk. There were no differences in UE strength (all p≥0.22). Natives had more rest (natives 76.38%; non-natives 26.86%; p=0.002) and less muscle tension (natives 11.53%; non-natives 48.60%; p=0.008) for non-dominant upper trapezius across the first minute of the trial. For ballistic signing, no differences were found in resultant linear segment acceleration when producing the sign for ‘again’ (natives 27.59m/s2; non-natives 21.91m/s2; p=0.20). For non-neutral joint angle, natives had more wrist flexion-extension motion when producing the sign for ‘principal’ (natives 54.93°; non-natives 46.23°; p=0.04). Work envelope demonstrated the greatest significance when determining injury-risk. Natives had a marginally greater work envelope along the z-axis (inferior-superior) across the first minute of the trial (natives 35.80cm; non-natives 30.84cm; p=0.051). Natives (30%) presented with a lower pain prevalence than non-natives (40%); however, there was no significant difference in the modified SI scores (natives 4.70 points; non-natives 3.06 points; p=0.144) and no association between presence of pain with the modified SI score (r=0.087; p=0.680). This work offers a comprehensive analysis of all the previously identified UE biomechanics unique to signers and helped to inform a composite measure of injury-risk. Use of the modified SI demonstrates promise, although its lack of association with pain does confirm that injury-risk encompasses other variables in addition to a signer’s biomechanics. / Dissertation/Thesis / Doctoral Dissertation Exercise and Nutritional Sciences 2018

Title: Compensatory exercise in synchronized swimming Aims: The aim of this diploma thesis is to find out the effect of movement intervention on compensating the deviations in the posture related to muscle imbalance and to influence the feeling of muscular tension of the back muscles in the girls of synchronized swimming TJ Tábor. Methods: The diploma thesis is elaborated by the form of qualitative research with elements of quantitative research. The experiment was attended by eight probes with deviations in the posture. A physical intervention in the form of compensatory exercise was introduced to influence the muscular dysbalance in the fuselage region. The research was conducted from October 2016 to May 2017. The research methods consisted of the examination of aspects using a plumb line in the sagittal and frontal plane. Depending on the subjective sensation, probands marked the muscular tension of the back muscles on the modified VAS. Results: The obtained data were processed by the statistical method (relative analysis). The results showed a positive effect on the body's position in the sagittal and frontal plane. Interventions also positively influenced subjective feelings of muscle tension. Keywords: synchronized swimming, posture, compensatory exercise, muscle tension, VAS modification

The differences among certain physiological changes occurring in response to mirthful laughter, directed relaxation, and verbal speech were investigated. These changes included amount of muscle tension, as measured with surface electromyography, in the forehead and in the upper body as recorded from the forearms bilaterally, peripheral surface skin temperature, heart rate, and respiration rate. The study sought to determine whether the net effect of laughter, as measured on these five variables after a three-minute refractory period, is a more relaxed state than existed before the laughter. Determination of the similarity between the changes following laughter and the changes following directed relaxation was made in comparison with the changes following verbal speech. Factors of prior anxiety, pre- and post-self-esteem levels, humor level, and laughter intensity were examined. Historical and theoretical perspectives were reviewed, as well as the known information on physiological responses to laughter.