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EN
Background: Hyperbaric therapy is a relatively new non-invasive therapeutic method. It involves inhaling the patient with pure oxygen using a pressure of 2 to 3 absolute atmospheres (ATA). The main purpose of this therapy is to improve the healing mechanisms and repairing processes in the case of various types of wounds and diseases. While in medicine this method is quite popular, in sport it is rarely used today and if so than mainly for the purposes of faster return to full fitness of athletes after injuries or after heavy, intense training conditions. Case study: Two subjects took part in the experiment. Training sessions were performed based on the selected original set of exercises within 29 days. Experiment participant was under conditions of increased pressure (2.5 ATA), during the session he breathed 100% oxygen, provided by the individual respiratory system. The measurement of muscle strength level of selected muscle groups, in selected motor tasks was estimated in (maximum weight – which is the maximum external resistance defeated in one repetition). It was found that there were increases in the level of muscle strength in selected muscles groups in first participant as a result of the applied set of exercises (motor tasks) and the effect of the hyperbaric sessions. Conclusions: The results of the study show that there was a visible/significant influence of the hyperbaric session on increasing the muscle function based on strength training example. This method in combination with adequate strength training sessions could be used in many areas connected with psychomotor development of human abilities.
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EN
Purpose. The literature shows few studies on shod and unshod running performance in athletes, with most limited to laboratory settings. The aim of this study was to evaluate preadolescent 1000 m running performance when barefoot and in running spikes or training shoes. Methods. A sample of 22 boys and 21 girls aged 10.6 ± 1.1 years was recruited. Anthropometric data and VO2max were recorded when completing the three study protocols in a counter balanced design. Student’s t tests were applied to compare mean 1000 m finish times while ANOVA was used to evaluate sex differences between the protocols. Pearson's correlation analysis measured interactions between the finish times, anthropometric variables, and VO2max. Results. Running performance with spikes (4.58 min) was significantly better than with training shoes (5.21 min) and barefoot (5.18 min). Male 1000 m times were overall better than the females. A substantial effect of VO2max and body fat on performance was found in all protocols. Conclusions. Preadolescent endurance performance was not significantly different between training shoes and barefoot; this may serve as an incentive for future research on the training of developmental age runners.
Human Movement
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2008
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vol. 9
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issue 1
56-61
EN
Purpose. The purpose of this paper is to present a simple, table-graphic model of one-to-one play in soccer based on observation of cooperation of top soccer players. Basic procedures. The research material consisted of audio-visual recordings from six soccer matches played by the three top teams of the 2006 World Cup finals. The data concering one-to-one plays was entered on a special form. Offensive and defensive actions were assessed with reference to the implementation of the game's objectives and players' position in the field zones. Main findings. It has been proven that elite soccer players are most effective at intercepting the ball down the field and in other zones of the pitch. They are also very active in breaking their opponents' offensive actions in midfield. Conclusions. The models reflecting elite soccer players' efficiency in one-to-one play should constitute important references for the training of novice soccer players.
EN
Background: The aim of this research was an attempt at qualifying the influence of various kinds of warm-up on physical effort ability, as well as examining whether there exists any dependence between the surface temperature of the quadricipital muscle of the thigh and the power expressed with the height of counter movement jump (CMJ). Material/Methods: In the research thermographic imaging and dynamometric platform were used. The subjects performed the CMJ test in 3 separate sessions - without any warm-up and then after preparation (1st session - jogtrot; 2nd session - jogtrot and stretching exercises; 3 session - dynamic warm up exercises). Results: In the examined group there was no lineal dependence between the surface temperature of the quadriceps and the power expressed with the height of a jump. Regardless of the kind of the applied warm-up, subjects improved their own results in the CMJ test; however, no such regularity concerning the temperature rise on the surface of a muscle was observed. In a dynamic warm-up lower surface temperature of the quadriceps meant a higher value of CMJ (r=0.64; p<0.05). This warm-up proved to be most efficient in the preparation for effort. Conclusions: The fact that highest values of a jump and surface temperature were attained after various kinds of warm-up permits supposing that finding individual forms of preparation for effort by an athlete, in order to increase the competition efficiency, is possible.
Human Movement
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2012
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vol. 13
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issue 2
152-160
EN
Purpose. This study aimed at determining what relationships exist between the determinants of team play efficiency (cooperation) for creating scoring situations in volleyball and the sporting level of a team. These relationships take into consideration the number of players who cooperate within a team and the speed at which sets are performed. Methods. The study gathered observational data on how three leading male volleyball teams, namely Brazil, Russia and Serbia, played in the semi-finals of the 2010 World League, finishing first, second and fourth, respectively. The research tool was a self-made data registration sheet which included the description of the chosen variables, namely the type of plays used and how sets were formed, and the criteria for their quantification. The collected results were presented as tables and indexes. An interdisciplinary interpretation of the results was conducted, which included a qualitative identification of the dependencies that existed between the chosen variables. Results. The efficiency of team cooperation when solving situational problems in the offense was not significantly different in the analysed teams. The prevailing activities during the game were those performed in the 2nd tempo, i.e. team play requiring the coordination and synchronization of three players. Players' activity as well as the performance efficiency of the sets they performed in the 2nd tempo increased along with an increase in the sporting efficiency of the examined teams. In the case of sets performed in the 3rd tempo, activity and the efficiency of coordination declined along with the growth of sports efficiency. The suggested indexes of the employment and application of synergy enable us to determine its level within the teams which differ in regards to sports efficiency. A diagnostic value of the index of synergy usage, which is determined by the efficiency of sets in various paces, is higher than a diagnostic value of the index that is determined by the activity of team play. Conclusions. Nowadays, sport teams, especially those which play volleyball at the highest world level, are characterized by a high level of dynamic organization of players' activities, which is manifested in the game with the high efficiency of team play when solving situational problems in the offense, particularly with the use of two or three players conducted in the 1st and 2nd tempos.
EN
This paper presents an experimental investigation of two incline solar water desalination (ISWD) systems. One design uses spray jets for spraying water onto the absorber plate, while the other uses a longitudinal slot for getting the inlet water on the absorber plate. The first ever ISWD system constructed and tested by Aybar et al (2005) used the longitudinal slot with a maximum daily production of 2.995 kg/m2 day. The Aybar et al design produced 3.4 kg/m2-day while the new design produced 6.41 kg/m2-day for wick on absorber plate system day during the hottest months in Famagusta (July-August 2010). Also tested was the influence of porous media (wire mesh), wick on the absorber plate. The effect of number of spray jets used in the system on the daily productivity and efficiency of the systems were also investigated.
EN
INTRODUCTION: For firefighters to respond effectively and safely in challenging situations, their protective gear must offer maximum protection, comfort, and ergonomics. While this gear protects against high temperatures, it can pose risks in other scenarios. Specialised attire safeguards against fires but can be perilous in localised threats, potentially life-threatening. This is associated with increased internal body temperature, causing rapid breathing, elevated heart rate, increased blood flow and pressure, substantial sweating, and loss of essential elements. The study aimed to compare physical stress levels at high and low ambient temperatures and examine the variations in measured parameters. MATERIAL AND METHODS: This study assesses how working in high temperature conditions wearing firefighter gear affects physical and psychological abilities and recovery between tasks. It evaluates participants' well-being before and after the study, years of service, protective gear comfort, fluid intake, alternatives to standard gear, and recovery time. It uses questionnaires and measurements of vital signs (body temperature, weight, blood pressure, oxygen saturation, heart rate) before and after physical exertion. RESULTS: A total of 152 participants participated in this study, with 30 during the winter season and 122 in the summer. The human body releases heat through convection, conduction, radiation, and evaporation. Maintaining normothermia is challenging at high temperatures. In summer, participants' weight increased due to sweating. After exertion, blood pressure diverged significantly, with the summer group showing a notable increase in systolic pressure, which stressed the need for hydration. Blood oxygen levels increased during exertion but normalised after rest. Pulse rates were similar at rest but significantly increased in the summer group after exertion, highlighting the importance of caution and hydration at high temperatures. CONCLUSIONS: Analysis of collected data, including medical assessments and surveys, clearly demonstrates the significant impact of working in high temperature conditions on the vital parameters of the participants. Prolonged heat exposure, primarily due to the insulating properties of specialised gear and resulting thermal discomfort, accelerates fatigue and exhaustion. This, in turn, leads to increased errors, slower responses, and potential health problems. To address this concern, the introduction of lighter uniform options, adjustments to legal regulations, and the inclusion of overheating risks in medical protocols should be considered as preventive measures.
EN
This study compared two different body positions at the finish of a stroke during stationary rowing exercise on physiological and kinematic measurements. Nine male and five female rowers volunteered for the study: mean age (± SD), body height and body mass were 27 ±9 yrs, 180.5 ±12.3 cm and 81.2 ±14.2 kg. The two body positions at the finish were controlled at an upright posture or a novel greater lean back position. All subjects completed 3 different experimental trials on a Concept IID rowing machine at 3 different exercise intensities and comparisons were made between the lean back position at the same stroke rate and the same power output as the upright trial. Power output, heart rate, oxygen uptake, energy expenditure and % efficiency were higher (p<0.05) with the greater lean back position at the same stroke rate compared to all other conditions. Range of motion at the hip, ankle, and elbow and the handle velocity and distance moved were greater (p<0.05) with the lean back position. In conclusion, a greater lean back posture at the finish during stationary rowing produces a higher power output and improved efficiency at the same stroke rate but at an elevated physiological cost compared to a more upright position. Despite the higher energy expenditure, the relative gain in power output and efficiency with no negative kinematic changes suggests that a greater lean back position at the finish will enhance performance during stationary rowing exercise.
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