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EN
The main objective of the work was to evaluate the influence of a six day supplementation with sodium phosphate on circulatory and pulmonary variables, the level of 2,3-diphosphoglycerate (2,3-DPG) and the concentration of inorganic phosphates in blood serum of elite off-road cyclists. The research material included 19 cyclists which were randomly divided into a experimental group, supplemented with sodium phosphate and a control group receiving a placebo The subjects in the experimental group ingested sodium diphosphate in a dose of 50mg/kg of fat free mass per day. The supplement was ingested in even doses, four times per day. The control group received 4g of glucose in gelatin capsules (500mg), which were also divided into 4 even portions. During the experiment a significant (p<0.05) increase in maximal oxygen uptake was observed (VO2max), maximal minute ventilation (VEmax), as well as oxygen pulse (O2/HR). Also a significant decrease in resting and maximal exercise heart rate occurred. This was also true for each exercise load. A significant (p<0.05) increase in the serum concentration of non-organic phosphates (P) was observed which was accompanied by a decrease in serum calcium (Ca) concentration. The changes in the resting and post exercise concentration of 2,3-DPG were non significant, yet the supplementation procedure showed a tendency for increased level of this variable.
EN
The main objective of this study was to investigate the effects of alkaline creatine supplementation and resistance training termination on anaerobic power and chosen biochemical variables in men. Twenty-three untrained male subjects, which participated in this study, were divided into supplemented (S) (n=13, age 21.4±2.3 y) and placebo (PL) (n=10, age 22.1±2.6 y) groups. The participants from both groups performed resistance training 3 times a week, while subjects from group S were supplemented with alkaline creatine (ACr) for 4 weeks on their training day's with 66.8 mg/kg b.m., and on non training day's with 33.8 mg/kg b.m.To evaluate anaerobic power, the 30s Wingate test was applied. The following variables were registered: relative mean power - RMP (W/kg), relative peak power - RPP (W/kg), time of reaching peak power - TRPP (s) and relative total work - RTW (J/kg). The test was administrated 5 times - before and after 4 weeks of training and supplementation, as well as the first, second and third week after terminating creatine intake and the resistance exercise protocol. Body mass and body composition was also evaluated during the same time span. Blood samples were drawn at rest before the Wingate test for the assessment of IGF-1, hGH, LA and CrN concentration, as well as creatine kinase (CK) and lactate dehydrogenase (LDH) activities. Supplementation with alkaline creatine, combined with a progressive resistance training program, did not significantly influence (ANOVA) the level of RMP (p=0.49), RPP (p=0.31), TRPP (p=0.51), and RTW (p=0.58) in untrained male subjects. In the supplemental group, there was a significant decrease (p<0.01) in TRPP following creatine supplementation and training, yet these values were not significantly different from the control group. The supplementation and training protocol did not influence significantly body mass (p=0.68), yet post hoc analysis indicate a significant increase in body mass (p<0.001) only in group S. The applied supplementation and training protocol did not influence (ANOVA) the concentration of serum CrN (p=0.81), hGH) (p=0.26), CK (p=0.49) and LDH (p=0.64) activities. No significant changes were observed in resting blood LA concentrations of the tested subjects. It can be concluded that the ergogenic effect of creatine intake and resistance training was maintained for a week after terminating supplementation and exercise. During the next 2 weeks de-adaptation occurred and most indices of anaerobic power returned to initial values.
EN
The cytotoxicity of chitosan with polyvinox (PCH) and crosslinked chitosan (CH) was studied and analyzed. Cell viability was determined by thiazolyl blue formazan (MTT) assay and cell morphology observations were carried out during cell culturing and MTT tests. Crosslinked chitosan was used as a protective foil (scaffold) for skin wounds. Studies in vitro and the other obtained in this work results prove that the studied materials CH and PCH do not cause cytotoxic activity to Balb 3T3 mouse fibroblasts. CH and PCH are promising biomaterials with prospective application as wound healing dressings.
EN
Resistance exercise is a popular form of conditioning for numerous sport disciplines, and recently different modes of strength training are being evaluated for health benefits. Resistance exercise differs significantly in nature, and several variables determine the direction and range of adaptive changes that occur in the muscular and skeletal system of the body. Some modes of resistance training can also be effective in stimulating the cardiovascular system. These variables include exercise selection (general, specific, single or multi joint, dynamic, explosive), type of resistance (free weights, variable resistance, isokinetics), order of exercise (upper and lower body or push and pull exercises), and most of all the training load which includes intensity expressed as % of 1RM, number of repetitions, number of sets and the rest interval between sets. Manipulating these variables allows for specific adaptive changes which may include gains in muscle mass, muscle strength or muscle endurance. It has been well established that during resistance exercise fatigue occurs, regardless of the volume and intensity of work applied. The peripheral mechanisms of fatigue have been studied and explained in more detail than those related to the CNS. This review is an attempt to bring together the latest knowledge regarding fatigue, both peripheral and central, during resistance exercise. The authors of this review concentrated on physiological and biochemical mechanisms underlying fatigue in exercises performed with maximal intensity, as well as those performed to exhaustion with numerous repetitions and submaximal load.
EN
Introduction: Resistance towing is perhaps the most specific form of developing strength and power in muscles involved directly during the start, acceleration and at maximum speed. Resisted sprint training may involve towing a sled which provides an overload through the friction between the sled and ground surface or a modern advanced training device which uses drag technology to provide fully controlled resistance during the movement, such as the 1080 Sprint. The main objective of the study was to evaluate the optimal loading for the development of power in the engine assisted drag technology system SPRINT 1080. Material and methods: We evaluated the changes in running velocity and the generated force and power during resisted sprints over 30m with a load of 1, 3, 6, 9, 12 and 15 kg. Seven male sprinters with national and international experience participated in the study. Their average age, body mass and body height were 22.2 ± 2.4 years, 77.43 ± 4.63 kg, and 178.6 ± 3.2 cm, respectively. All athletes performed six 30 m sprints with 5 min rest intervals in between. The first sprint was performed without additional resistance, while the remaining 5 were performed in an random order with additional resistance of 3, 6, 9, 12 and 15 kg. After receiving a verbal signal, the participant started at will from a semi crouched position. During the resisted sprint trials, the time [s] and the following variables were recorded in peak values: power output [W], generated force [N], and sprinting velocity [m/s]. Results: Our results show that loading with 6 kg decreased sprinting velocity by 9.37% while the generated horizontal power increased by 31,32%. The 6 kg loading on the Sprint 1080device corresponded to 8% body mass, yet as mentioned before the baseline results were not fully free sprinting as the tested athletes reached velocities 0.5-0.6 m/s greater without the harness. Conclusion: Taking into account this fact, our results seem to confirm previous findings, that external loads between 8 and 13% may be optimal for improving power and sprinting speed at the same time.
EN
The Maximal Lactate Steady State (MLSS) is defined as the highest workload that can be maintained over time where there is a balance between lactate production and lactate clearance. Therefore, determination of this workload is very importance for diagnosis of aerobic capacity and training program design.The main objective of this study was to evaluate the validity of lactate threshold values determined by the D-max method as related to MLSS in cyclists. The research material included 10 female (body height 167±5.7 cm; body mass 56±4.8 kg; percent body fat 12.3±2.1) and 10 male well-trained cyclists (body height 183.5±4.4 cm; body mass 73.2±4.1 kg; percent body fat 7.9±2.6). The research had two distinct phases, separated by one day of active recovery. During the first phase, progressive tests were carried out to determine lactate threshold and maximal oxygen uptake in each subject. During the second phase, each athlete performed a series of 30-min ergocycle tests, with a fixed workload to establish maximal lactate steady state.Results showed no significant differences between lactate threshold workload (WRLT), determined by the D-max method, and maximal lactate steady state workload (WRMLSS) in female and male cyclists, expressed in absolute and relative values. Differences between male and female cyclists in absolute and relative values of WRLT, WRMLSS, and WRmax were significant (p<0.05), but in relative values there was a tendency for decreased differences between groups. The oxygen uptake at the lactate threshold and MLSS were significantly (p<0.05) different. Also, a significant (p<0.05) difference was observed in values of heart rate and lactate concentration at the lactate threshold and MLSS. The analysis of changes in lactate concentration, heart rate and oxygen uptake between the 10th and 30th minutes of MLSS, indicates that there was a significant (p<0.05) increase in these values in male and female cyclists. The strong correlation (r=0.97; p<0.05) between WRLT and WRMLSS was found. Also, a significant correlation between (r=0.96; p<0.05) WRMLSS and peak workload during the incremental test (WRmax) (r=0.96; p<0.05) was also observed.
EN
The aim of the present study was to evaluate the efficacy of 3-week high intensity interval training in normobaric hypoxia (IHT) on aerobic capacity in basketball players. Twelve male well trained basketball players, randomly divided into a hypoxia (H) group (n=6; age: 22±1.6 years; VO2max: 52.6±3.9 ml/kg/min; body height - BH: 188.8±6.1 cm; body mass - BM: 83.9±7.2 kg; % of body fat - FAT%: 11.2±3.1%), and a control (C) group (n=6; age: 22±2.4 years; VO2max: 53.0±5.2 ml/kg/min; BH: 194.3 ± 6.6 cm; BM: 99.9±11.1 kg; FAT% 11.0±2.8 %) took part in the study. The training program applied during the study was the same for both groups, but with different environmental conditions during the selected interval training sessions. For 3 weeks, all subjects performed three high intensity interval training sessions per week. During the interval training sessions, the H group trained in a normobaric hypoxic chamber at a simulated altitude of 2500 m, while the group C performed interval training sessions under normoxia conditions also inside the chamber. Each interval running training sessions consisted of four to five 4 min bouts at 90% of VO2max velocity determined in hypoxia (vVO2max-hyp) for the H group and 90% of velocity at VO2max determined in normoxia for the group C. The statistical post-hoc analysis showed that the training in hypoxia caused a significant (p<0.001) increase (10%) in total distance during the ramp test protocol (the speed was increased linearly by 1 km/h per 1min until volitional exhaustion), as well as increased (p<0.01) absolute (4.5%) and relative (6.2%) maximal workload (WRmax). Also, the absolute and relative values of VO2max in this group increased significantly (p<0.001) by 6.5% and 7.8%. Significant, yet minor changes were also observed in the group C, where training in normoxia caused an increase (p<0.05) in relative values of WRmax by 2.8%, as well as an increase (p<0.05) in the absolute (1.3%) and relative (2.1%) values of VO2max. This data suggest that an intermittent hypoxic training protocol with high intensity intervals (4 to 5 x 4 min bouts at 90% of vVO2max-hyp) is an effective training means for improving aerobic capacity at sea level in basketball players.
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Time Series Approach To Athletes Motor Potential

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EN
Introduction. The aim of this study was to determine the dynamics of changes in selected motor abilities of javelin throwers and to determine predictors of javelin throw distances. Material and methods. Research material included the results obtained from a group of 60 competitors from the Silesia Region of Poland, aged 14 - 15 years. In order to answer the research question, the following statistical analysis were employed: Pearson's linear correlation coefficients, vectors R0 and R1, time series analysis, distributed lag analysis and Almon distributed lag analysis and coefficient of concordance φ2Results. The correlation analyzes allowed for a selection of two variables for further analyses: specific strength of arms and trunk (SSAT) and specific strength of shoulders girdle and trunk (SSGT). Calculated indexes revealed that the level of SSAT showed a constant upward tendency (+15%). The highest rise in SSAT level was recorded in the 4th and 5th quarter (+9%). The level of SSGT showed an upward tendency nearly (+6%). In this case, the highest rise was observed in the 7th and 8th quarter (+4.5%). Conclusions. The standardized regression analysis revealed that the variable of specific power of arms and trunk (SOBT) is the most important predictor for javelin throw distance with a full approach run.
EN
This paper analyses the dynamics of changes between the performances of elite freestyle swimmers recorded at particular Olympic Games. It also uses a set of chronologically ordered results to predict probable times of swimmers at the 2012 Olympic Games in London. The analysis of past performances of freestyle swimmers and their prediction have revealed a number of interesting tendencies within separately examined results of men and women. Women's results improve more dynamically compared with men's. Moreover, the difference between women's and men's results is smaller, the longer the swimming distance. As both male and female athletes tend to compete more and more vigorously within their groups, the gap between the gold medallist and the last finisher in the final is constantly decreasing, which provides significant evidence that this sport discipline continues to develop.
EN
The aim of this study was to evaluate the effects of steroidal saponin supplementation on blood concentration of T, GH and IGF-1. The research involved 14 men between the age of 45 and 60 years. The duration of the experiment was 12 weeks. There were two series of laboratory tests. Independent tests were conducted at the beginning and after 12 weeks of the intervention. A two-way repeated measures ANOVA revealed a statistically significant effect of the intervention on the following variables: T-Ch (η2 = 0.542), HDL-Ch (η2 = 0.522), LDL-Ch (η2 = 0.587), T (η2 = 0.603), IGF-1 (η2 = 0.512) and GH (η2 = 0.621). Thus, FFM significantly increased while TBF and BM decreased in comparison to pre-intervention levels. The analyzed results indicate that treatment or supplementation of individual hormone deficiencies can be a successful form of counteracting the aging process. Nevertheless, the effects of TT supplementation on the concentration of T as well as GH and IGF-1, requires further studies, especially in middle-aged and older subjects, along with different exercise programs. The analyzed results indicate that treatment or supplementation of individual hormone deficiencies can be a major form of counteracting the aging process.
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