Comparison of the Cardiovascular Effects of Extreme Psychological and Physical Stress Tests in Male Soccer Players

Background: The purpose of our study was to compare the physiological effects of extreme physical and psychological stress tests in male soccer players, since these two types of stress apply to athletes with high performance requirements. Methods: A total of 63 healthy male soccer players participated in this study, all of whom underwent both of the tests. A physical stress test was carried out in an exercise physiology laboratory, where subjects completed an incremental treadmill running test to full exhaustion, and a psychological test was performed in a military tactical room, where subjects met a street offence situation. Heart rate variability (HRV) and blood pressure (BP) were recorded directly before, immediately after, and 30 min after the stress tests. Results: The majority of HRV indices changed significantly in both stress protocols. Inverse, significant changes (positive for the physical test, negative for the psychological test, p < 0.001) were found when comparing the alterations of HRV indices between the tests. Significant differences were found in the changes in systolic (p = 0.003) and diastolic (p < 0.001) BP between the test protocols, and also between the baseline and post-test measurements (p < 0.001). Conclusion: Both HRV and BP are sensitive physiological parameters to measure the impact of extreme physical and/or psychological stress

EFFECTS OF PHYSICAL STRESS ON VISUAL ACUITY IN THE PLAIN AND MOUNTAIN CONDITIONS

Научная статья посвящена установлению изменений со стороны зрительных функций у студенток старших курсов очно-заочной формы обучения в условиях гипоксической и динамической гипоксии. В период акклиматизации к гипоксической гипоксии в течение пятнадцати дней наблюдалась волнообразность или двухфазность изменения остроты зрения. Повышение с первого по пятый день и постепенное снижение с десятого по пятнадцатый день. Scientific article is devoted to establishing changes on the part of visual functions in students of senior courses of full-time education in conditions of hypoxic and dynamic hypoxia. During the period of acclimatization to hypoxic hypoxia, waviness or two-phase change in visual acuity was observed for fifteen days. Increase from day one to day five and gradual decrease from day ten to day fifteen.

Development and testing of a tool for the decontamination of corners and inner edges on concrete surfaces

For the decontamination of flat concrete surfaces, a wide variety of tools are available; however, these tools cannot be used for the decontamination of corners, inner edges, gaps and other geometrical discontinuities. Currently, these areas are worked by hand-held tools with a connected vacuum exhaust system to reduce dust emissions. The combination of using heavy hand-operated tools with exhaust systems on difficult to access areas as well as the forces and vibration of the tools, make the task of decontamination a burden and add additional physical stress for the operator. The goal of the research project called EKont, funded by the German Ministry for Education and Research, BMBF), is, to develop an innovative semi-automated demonstrator for dry mechanical decontamination of corners, edges and geometrical discontinuities in nuclear facilities. The tool will have a flexible housing with an integrated exhaust system to reduce the dust load. This specialized tool should make the decontamination of corners and inner edges more effective regarding time and the generation of secondary waste and should further spare the musculoskeletal system of the operator physical stress by lowering the vibrations and weight of the tool. For this task, a test bench for testing and evaluating different methods of surface decontamination has been set up. The test bench enables the measurement of forces and vibrations of the machine during the decontamination and the dust emissions. Based on the analysis of different decontamination methods and tools, four prototypes are being developed. This project also aims at the scientific investigation of experimentally collected performance parameters, such as feed rate, removal depth per operation, surface roughness and removal rate, in order to determine the relevant parameters of the developed prototypes. A field test of the prototypes together with decommissioning companies is scheduled. The prototype is not limited to use in nuclear facilities but later can also be used in conventional fields, for example in the decontamination of materials containing PCBs and asbestos. In this presentation the EKont test bench and prototypes will be explained and the test results will be presented.

Asymptomatic takotsubo syndrome occurring during Holter monitoring

Asymptomatic takotsubo syndrome was observed during periodic Holter monitoring in a man in his 60s undergoing maintenance dialysis. No emotional or physical stress was noticed. The electrocardiographic changes at onset were determined, and repeated ST elevation and progressive formation of giant negative T waves were recorded.

Training vs. Competition in Sport: State Anxiety and Response of Stress Hormones in Young Swimmers

This study was aimed to assess the neuroendocrine response to stress induced by different sports environments (a regular training session and a competitive event), to define the contribution of psychological and physical stress, and to check the possible relationship between state-anxiety and stress hormones responses to competitive and non-competitive sports practices. Twelve young national-level male swimmers participated in this investigation. Endorphins, adrenocorticotropin, and prolactin plasma levels were measured at baseline conditions (t0), before a regular swimming training session (t1), and before and after real swimming competition consisting of 100 m freestyle (t2 and t3, respectively). Moreover, state-anxiety was evaluated in all assessment time-points. The results showed no differences in endorphin, adrenocorticotropin, prolactin and state-anxiety between t0 and t1; however, significant increases in endorphins (142%), prolactin (137%) and state-anxiety (13%) were observed in t2. Huge stress response was observed in t3 (increases of 354%, 387%, and 250% for endorphins, adrenocorticotropin, and prolactin, respectively) although state-anxiety decreased slightly. Lastly, a lack of the relationship between stress hormones and state-anxiety was found in all conditions. Mental and especially physical stress associated with sports competition induces a significant release of stress hormones which is not relevant for the regular training session.