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On Quasi-equivalence of Quasi-free KMS States restricted to an Unbounded Subregion of the Rindler SpacetimeKähler, Maximilian 26 October 2017 (has links)
The Unruh effect is one of the most startling predictions of quantum field theory. Its interpretation has been controversially discussed, since the first publications of Fulling, Davies and Unruh in the 1970ties. In a recent paper Buchholz and Solveen proposed an application of basic thermodynamic definitions to clarify the meaning of temperature and thermal equilibrium in the Unruh effect. As a result the interpretation of the KMS-parameter as an expression of local temperature has been questioned. The main result of my diploma thesis asserts quasi-equivalence of the disputed KMS states on a subregion of Rindlerspace that infinitely extends in the direction of travel of a uniformly accelerated Rindler-observer. Exploring the consequences of this result, I will present new insights on the asymptotic behaviour of such KMS states and how this fits into the picture drawn by Buchholz and Solveen.
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Vliv celotělové elektromyostimulace na svalovou sílu a tělesné složení u zdravých jedinců / The influence of whole-body electromyostimulation on muscle strength and body composition in healthy individualsKamarýtová, Magdaléna January 2020 (has links)
Title: The influence of whole-body electromyostimulation on muscle strength and body composition in healthy individuals Objectives: The aim of the diploma thesis is to collect and give comprehensive theoretical information concerning the whole body electromyostimulation topic. Furthermore, find out what the effect of the whole body electromyostimulation method on body weight, fat-free mass, body fat and other parameters of body composition. The aim of this work is to verify whether it is possible to achieve changes in bone mineral density values by means of the WB-EMS method or to increase maximal isometric muscle strength in healthy individuals. Methods: The diploma thesis is an intragroup experiment. The method of qualitative research was used for data collection. Bioelectric impedance analysis was used to evaluate body composition. DXA (Dual Energy X-Ray Absorptiometry) was used to assess bone mineral density and body composition, and isometric muscle strength was evaluated using isometric dynamometry. The research group consisted of 10 young and healthy probands (average age 23.9 years). Probands completed 10 exercise units using the whole body electromyostimulation method. The frequency of exercise was once a week. Results: We have found that after ten weeks of using the whole-body...
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Shape Spaces and Shape Modelling: Analysis of planar shapes in a Riemannian frameworkKähler, Maximilian 16 April 2018 (has links)
This dissertation presents some of the recent developments in the modelling of shape spaces. Forming the basis for a quantitative analysis of shapes, this is relevant for many applications involving image recognition and shape classification. All shape spaces discussed in this work arise from the general situation of a Lie group acting isometrically on some Riemannian manifold. The first chapter summarizes the most important results about this general set-up, which are well known in other branches of mathematics. A particular focus is laid on Hamiltonian methods that explore the relation of symmetry and conserved momenta. As a classical example these results are applied to Kendall’s shape space. More recent approaches of continuous shape models are then summarized and put in the same concise framework. In more
detail the square root velocity shape representation, recently developed by Srivastava et al., is being discussed. In particular, the phenomenon of unclosed orbits under the action of reparametrization is addressed. This issue is partially resolved by an extended equivalence relation along with a well defined, non-degenerate, metric on the resulting quotient space.
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Comparing Muscle Hypertrophy and Myosin Heavy Chain Content Between Relative Intensity and Repetition Maximum Resistance TrainingCarroll, Kevin M., Bernard, Jake R., Stone, Michael H. 01 January 2017 (has links)
Abstract available in the Medicine and Science in Sports and Exercise.
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The Use of the Isometric Mid-thigh Pull in the Monitoring of Weightlifters: 25+ Years of ExperienceStone, Michael H., O'Bryant, Harold, Hornsby, Guy, Cunanan, Aaron, Mizuguchi, Satoshi, Suarez, Dylan, South, Mark, Marsh, DJ, Haff, Gregory, Ramsey, Michael, Beckham, George, Santana, Hugo, Wagle, John, Stone, Margaret, Pierce, Kyle 01 January 2019 (has links)
Currently, multi-joint, position-specific isometric tests (MJIT) are commonly used as part of the monitoring of an athlete’s progress. Strong associations between isometric force-time curve parameters have been found. Perhaps the most commonly used test is the isometric mid-thigh pull (IMTP): the IMTP was created in the early 1990s and its use has grown considerably since that time. One sport in which it has been used extensively from the early 1990s to the present, particularly by the authors, is weightlifting. The relationships between weightlifting performance and IMTP force-time characteristics are quite strong, particularly for RFD. The IMTP is not only useful in assessing a weightlifter’s performance but can also be used for monitoring fatigue.
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Normativa styrkevärden i höftadduktorer och -abduktorer hos damfotbollsspelare på elitnivåKarlsson, Lynn January 2021 (has links)
Inledning: Muskelstyrka i höftregionen är en viktig fysisk färdighet inom fotboll dels ur ett prestationsperspektiv, dels för skadeprevention. Trots detta saknas normativa isometriska styrkevärden för höftadduktorer och - abduktorer hos damfotbollsspelare. Syfte: Syftet med denna tvärsnittsstudie var att undersöka den isometriska höftstyrkan i adduktion, unilateralt och bilateralt, samt höftabduktion unilateralt med en handhållen dynamometer hos skadefria damfotbollsspelare. Metod: 29 friska damfotbollsspelare på elitnivå inkluderades i studien. Den isometriska höftstyrkan mättes vid ett tillfälle på försäsongen med en handhållen dynamometer. Höftadduktion och -abduktion mättes unilateralt i en sidliggande position och den bilaterala höftadduktorstyrkan mättes i ett squeeze-test i en ryggliggande position. Ett tillägg av en extern fixation av dynamometern applicerades vid testtillfället. Resultat: Styrkevärden (medelvärde, SD ±) var: höftabduktion dominant ben 1,94 ± 0,3 Nm/kg, icke-dominant ben 1,81± 0,3 Nm/kg, höftadduktion dominant ben 1,61 ± 0,3 Nm/kg, icke-dominant ben 1,51 ± 0,3 Nm/kg, squeeze-test 4,11 ± 0,5 N. Styrkekvot adduktion/abduktion var 0,83 dominant ben och 0,84 icke-dominant ben. Det dominanta benet var signifikant starkare (p<0,05) i både höftadduktion och -abduktion, 7 % respektive 8 %. Konklusion: För damfotbollsspelare var det dominanta benet signifikant starkare i både höftadduktion och -abduktion. Höftabduktorerna var signifikant starkare än adduktorerna i både det dominanta och icke-dominanta benet med en styrkekvot adduktorerna/abduktorerna på 0,83 respektive 0,84. / Introduction: Hip strength is an important physical factor in soccer for both performance and for injury prevention. Despite this normative isometric strength values are lacking for hip adduction and abduction in healthy women’s soccer players. Aim: The aim of this cross-sectional study was to examine the isometric hip strength in adduction, unilateral and bilateral, and hip abduction unilateral with a handheld dynamometer in healthy women's soccer players. Methods: 29 healthy female elite soccer players were included in the study. The isometric hip strength was measured one time in the pre-season with a hand-held dynamometer. Hip adduction and abduction were measured unilaterally in a side lying position and the bilateral hip adductor strength was measured in a squeeze test in a supine position. An addition of an external fixation of the dynamometer was applied during testing. Results: Strength values (mean, SD ±) were: hip abduction dominant leg 1,94 ± 0,3 Nm/kg, non-dominant leg 1,81± 0,3 Nm/kg, hip adduction dominant leg 1,61 ± 0,3 Nm/kg, non-dominant leg 1,51 ± 0,3 Nm/kg, squeeze-test 4.11 ± 0.5 N. The strength ratio of adduction/abduction were 0,83 dominant leg and 0,84 non-dominant leg. The dominant leg was significantly stronger (p<0,05) in both hip abduction and adduction, 7 % and 8 %, respectively. Conclusion: For women’s soccer players the dominant leg was significantly stronger in both hip abduction and adduction. The hip abductors were significantly stronger than the adductors in both the dominant and non-dominant leg with a strength ratio adductor/abductor 0,83 and 0,84 respectively.
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Dynamic Strength Index: Relationships with Common Performance Variables and Contextualization of Training RecommendationsSuchomel, Timothy J., Sole, Christopher J., Bellon, Christopher R., Stone, Michael H. 31 August 2020 (has links)
The purposes of this study were to examine the relationships between dynamic strength index (DSI) and other strength-power performance characteristics and to contextualize DSI scores using case study comparisons. 88 male and 67 female NCAA division I collegiate athletes performed countermovement jumps (CMJ) and isometric mid-thigh pulls (IMTP) during a pre-season testing session as part of a long-term athlete monitoring program. Spearman's correlations were used to assess the relationships between DSI and CMJ peak force, height, modified reactive strength index, peak power and IMTP peak force and rate of force development (RFD). Very large relationships existed between DSI and IMTP peak force (r = -0.848 and -0.746), while small-moderate relationships existed between DSI and CMJ peak force (r = 0.297 and 0.313), height (r = 0.108 and 0.167), modified reactive strength index (r = 0.174 and 0.274), and IMTP RFD (r = -0.341 and -0.338) for men and women, respectively. Finally, relationships between DSI and CMJ peak power were trivial-small for male (r = 0.008) and female athletes (r = 0.191). Case study analyses revealed that despite similar DSI scores, each athlete's percentile rankings for each variable and CMJ force-time characteristics were unique, which may suggest different training emphases are needed. Based on the explained variance, an athlete's IMTP performance may have a larger influence on their DSI score compared to the CMJ. DSI scores should be contextualized using additional performance data to ensure each individual athlete receives the appropriate training stimulus during different training phases throughout the year.
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Phase- Specific Changes in Rate of Force Development and Muscle Morphology throughout a Block Periodized Training Cycle in WeightliftersSuarez, Dylan G., Mizuguchi, Satoshi, Hornsby, William Guy, Cunanan, Aaron J., Marsh, Donald J., Stone, Michael H. 28 May 2019 (has links)
The purpose of this study was to investigate the kinetic and morphological adaptations that occur during distinct phases of a block periodized training cycle in weightlifters. Athlete monitoring data from nine experienced collegiate weightlifters was used. Isometric mid-thigh pull (IMTP) and ultrasonography (US) results were compared to examine the effects of three specific phases of a training cycle leading up to a competition. During the high volume strength-endurance phase (SE) small depressions in rate of force development (RFD) but statistically significant (p ≤ 0.05) increases in vastus lateralis cross-sectional area (CSA), and body mass (BM) were observed. The lower volume higher intensity strength-power phase (SP) caused RFD to rebound above pre-training cycle values despite statistically significant reductions in CSA. Small to moderate increases only in the earlier RFD time bands (ms) occurred during the peak/taper phase (PT) while CSA and BM were maintained. Changes in IMTP RFD and CSA from US reflected the expected adaptations of block periodized training phases. Changes in early (ms) and late (≥150 ms) RFD time bands may not occur proportionally throughout different training phases. Small increases in RFD and CSA can be expected in well-trained weightlifters throughout a single block periodized training cycle.
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Effects of Three Lingual Conditions on Submental Muscle Activity in Healthy Young and Old AdultsOommen, Elizabeth R. 10 June 2013 (has links)
No description available.
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Comparisons Between Movement Onset Identification Methods Used in Isometric Mid-Thigh Pull TestLiu, Junshi 01 December 2018 (has links) (PDF)
This dissertation aimed to explore the usefulness of using force derivatives for onset detection in the isometric mid-thigh pull test. First, we examined applications of three differential calculus principles, first and second derivative, and curvature using visual detection as a reference under different baseline conditions. Second, we compared the best derivative method to a threshold-based method using visual detection as a reference. Results of our first investigation showed trivial differences between many differential calculus methods and visual detection. However, statistical differences exceeding a trivial effect was observed when instantaneous force and rate of force develop were examined. Through the first investigation, first and second derivative emerged as possible viable methods for baseline with a countermovement and for all other baseline conditions, respectively. Results of the second investigation showed similarities to the first investigation with respect to onset time. However, examination of instantaneous force and rate of force development indicated that a threshold-based method tended to overestimate compared to visual detection and a first and second derivative combined method. In fact, the difference between visual detection and the first and second derivative combined method ranged from trivial to moderate under all baseline conditions while the threshold-based method often reached a large difference. Overestimation by the threshold-method was more pronounced for rate of force development. In conclusion, while not perfect, the first and second derivative 3 combined method appears to hold possible practical potential and may be used as an assistant method for entry-level sport scientist plus using visual detection for obvious erroneous values.
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