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Background Potential health benefits are attributed to the antioxidant properties of green tea polyphenolic compounds. The main aim of the study was to evaluate the effects of a six-week green tea extract (GTE) supplementation combined with CrossFit workout on blood antioxidant status and serum brain-derived neurotrophic factor (BDNF) in men. Methods Sixteen young males involved in CrossFit training were randomized into two groups supplemented with GTE or placebo for six weeks. Each participant performed an exercise test for the evaluation of maximum oxygen uptake (VO2max) twice, i.e., before starting (1st trial) and after completing the supplementation combined with CrosFit workout (2nd trial). Venous blood samples were drawn at rest, immediately post-test and after one hour of recovery in order to estimate activities of antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], reduced glutathione [GR]), non-enzymatic antioxidants (reduced glutathione [GSH], uric acid [UA], total phenolics), total antioxidant capacity (FRAP), lipid peroxidation products (TBARS), and BDNF. Results Except for a significantly higher SOD activity and FRAP level recorded at rest and post-exercise in the 2nd trial compared to the corresponding values in the 1st trial, no significant differences were recorded among other assayed measures such as CAT, GPx, GR, GSH and BDNF. Moreover, a percentage increase in FRAP level was twice as high after six weeks’ GTE consumption than after placebo. Regardless of the trial, an increase in plasma UA concentration and a decrease in plasma total phenolics level were observed after exercise test. Plasma TBARS concentrations were significantly higher in PLA group after six weeks’ CrossFit training, while in GTE group they were slightly lower compared to the corresponding values in the 1st trial. Moreover, there was a significant inverse correlation between FRAP and TBARS in the GTE-supplemented group (r = − 0.40, p

The study evaluated differences in response to exercise stress between endurance and high-intensity intermittent trained athletes in a thermoneutral environment using a physiological strain index (PSI). Thirty-two subjects participated in a running exercise under normal (23°C, 50% RH) conditions. The group included nine endurance trained athletes (middle-distance runners - MD), twelve high-intensity intermittent trained athletes (soccer players - HIIT) and eleven students who constituted a control group. The exercise started at a speed of 4 km·h–1 which was increased every 3 min by 2 km·h–1 to volitional exhaustion. The heart rate was recorded with a heart rate monitor and aural canal temperature was measured using an aural canal temperature probe. The physiological strain index (PSI) and the contribution of the circulatory and thermal components to the overall physiological strain were calculated from the heart rate and aural canal temperature. The physiological strain index differed between the study and control participants, but not between the MD and HIIT groups. The physiological strain in response to exercise stress in a thermoneutral environment was mainly determined based on the circulatory strain (MD group - 73%, HIIT group – 70%). The contribution of the circulatory and thermal components to the physiological strain did not differ significantly between the trained groups (MD and HIIT) despite important differences in morphological characteristics and training-induced systemic cardiovascular and thermoregulatory adaptations.

The ongoing development of the modern society may also be easily noticed in sports. Currently, to be able to compete at the highest level at major sporting events, it is essential to conduct scientific research to estimate the individual potential and skill level of an athlete. The aim of this study was to assess the anaerobic endurance in men competing in the running events of 400 m/400 m hurdles based on the estimation of maximum power, as well as selected biochemical and physiological parameters measured in a cardiac stress test at a supramaximal intensity. Seven athletes participated in the study and were subjected to a modified version of the Wingate test (Bar-Or, Dotan, Inbar, 1997; Bar-Or, Inbar, Skinder, 1996) which involved performing three runs of a 12‑second endurance test on a cycloergometer at short intervals. This modification of the test allowed a more precise observation and a better understanding of the physiological and biochemical changes that decrease the efficiency as a result of repeated physical effort, which may significantly affect the assessment of the preparation of an athlete, and thus the assessment of the training process. The most significant changes in the course of the conducted study were observed in the values of the following biochemical parameters: glucose levels, acid–base balance of the blood and lactate levels.

Purpose. Physical activity is an integral part of the treatment of diabetes. The aim of the study was to assess aerobic capacity and cardiovascular-respiratory reactions to a single physical exercise with gradually increasing intensity in normobaric hypoxia in patients with Type 1 diabetes. Methods. The study was conducted on a sample of adults with Type 1 diabetes (GT1D, n = 13) and a randomly chosen healthy control (GK, n = 15). The study participants performed a progressive exercise test to exhaustion in normoxia (FiO2 ~ 20.90%) and 7 days later in normobaric hypoxia (FiO2 ~ 15.14%). At rest, during exercise, and after completion of the test blood was drawn and physiological indicators were monitored. Results. Two-way ANOVA revealed a significant effect of hypoxia and physical exercise on blood glucose concentrations (F = 6.1 p < 0.01). In GT1D , lower glucose levels were observed in normobaric hypoxia compared with baseline and post-exercise levels in normoxia (p < 0.05). A tendency to increased maximal oxygen uptake and significantly higher minute pulmonary ventilation was observed in both groups in response to exercise and hypoxia. Conclusions. Physical activity and hypoxia may effectively control glucose homeostasis and increase cardiorespiratory adaptation to exercise in Type 1 diabetics.

The aim of this study was to evaluate adrenergic responses in the peripheral blood of trained road cyclists at rest, at maximal intensity of incremental bicycle exercise test, and during 15 minutes of recovery, as well as the relationship between them. Competitive male road cyclists, in the pre-competitive phase of a season, mean age 21.7 ± 6.4 years, and BMI 20.7 ± 0.8 kg·m-2, performed an incremental test on a bicycle ergometer with unloaded cycling for 5 min, then increased the load to 40 W every 3 min, up to maximal exercise intensity. The plasma catecholamine concentrations (epinephrine, norepinephrine) and oxygen uptake were estimated. The expression of 132 genes related to the adrenergic system in leukocytes was measured. A statistically significant increase in plasma epinephrine concentration (p < 0.01) was observed in response to exercise. The mean of maximal oxygen uptake was 65.7 ± 5.5 ml·kg-1·min-1. The RGS2 gene expression was highest regardless of the test phase for all athletes. The effort had a statistically significant influence on ADRB2 and RAB2A expression. In addition, the RAB2A, ADM and HSPB1 expression level increased during recovery. We can conclude that plasma epinephrine concentration and genes related to the adrenergic system such as ADM, ADRB2, CCL3, GPRASP1, HSPB1, RAB2A, RGS2 and ROCK1 seem to have an influence on the response to high-intensity exercise in trained cyclists.

When investigating development potential, one should always take into consideration possible interactions among a variety of factors. Investigations of interactions that occur in the human body constitute a considerable contribution to further applications, which is particularly important in the case of disabled individuals and allows stimulation of the compensation processes in an oriented manner. The present study focuses on the effect of somatic growth on the level of aerobic/anaerobic capacities and their variability over time in hearing impaired children and adolescents. Correlations between somatic components and aerobic/anaerobic efficiency in hearing impaired individuals are compared to literature reports with regard to their normal-hearing peers. Our study has demonstrated that hearing loss does not modify interactions between the parameters of somatic growth and aerobic or anaerobic capacity of deaf children and adolescents. Thus, our results provide grounds for application activities based on neurophysiological growth patterns.

The physiological adaptation to training is specific to the muscle activity, dominant energy system involved,muscle groups trained, as well as intensity and volume of training. Despite increasing popularity of snowboarding onlylittle scientific data is available on the physiological characteristics of female and male competitive snowboarders.Therefore, the purpose of this study was to compare the aerobic capacity and maximal anaerobic power of elite Polishsnowboarders with untrained subjects. Ten snowboarders and ten aged matched students of Physical Educationperformed two exercise tests. First, a 30-second Wingate test was conducted and next, a cycle ergometer exercise testwith graded intensity. In the first test, peak anaerobic power, the total work, relative peak power and relative meanpower were measured. During the second test, relative maximal oxygen uptake and lactate threshold were evaluated.There were no significant differences in absolute and relative maximal oxygen uptake between snowboarders and thecontrol group. Mean maximal oxygen uptake and lactate threshold were significantly higher in men than in women.Significant differences were found between trained men and women regarding maximal power and relative maximalpower. The elite snowboarders demonstrated a high level of anaerobic power. The level of relative peak power in trainedwomen correlated negatively with maximal oxygen uptake. In conclusion, our results seem to indicate that thedemanding competition program of elite snowboarders provides a significant training stimulus mainly for anaerobicpower with minor changes in anaerobic performance.

Popularity of long-distance running has increased as well as number of female and male marathon runners. Whilst research into physiological characteristics of endurance trained athletes has significantly increased there are only few studies on the risk factors for respiratory failure in marathon runners. Therefore, the aim of the study was to evaluate the differences in respiratory function and the physiological strain in the response to exercise stress in marathon runners. Twenty three subjects (aged 36.1 ±11.6 years) participated in a marathon running. Prior to the run and after its completion, body mass and composition, spirometry and body temperature were measured. Based on pre- and post-run temperature and changes in heart rate, the physiological strain index (PSI) was calculated. Long-distance running significantly decreased the temperature of body surfaces (p < 0.05); no significant effects were observed regarding aural canal temperature and physiological strain index (PSI). Compared to resting values, post-marathon spirometry revealed a significant decrease in post-marathon forced expiratory volume (p < 0.05), peak expiratory flow (p < 0.05) and maximal expiratory flow values (p < 0.05). In conclusion, the long-distance running results in functional changes within the respiratory system which may limit the adaptive potential and decrease exercise tolerance.

The study aimed at evaluating changes in plasma levels of insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3), testosterone, growth hormone (GH), cortisol, and insulin in resistance-trained male athletes with (n=9) and without (n=9) left ventricular hypertrophy (LVH) in response to eccentric (ECC) and concentric (CON) arm exercise. 10 age-matched healthy non-trained subjects served as controls. M-mode and 2D Doppler echocardiography were used to estimate LV mass.Resting IGF-1 concentration was higher in LVH athletes compared to controls (52 ± 5 nM vs. 46 ± 7 nM, p

The study aimed to evaluate the effects of a 3-week n-3 polyunsaturated fatty acids (n-3 PUFA) supplementation on serum nitric oxide (NO), asymmetric dimethyloarginine (ADMA), ultrasound indices of endothelial function and maximal oxygen uptake (VO2 max) of elite cyclists. The effects of dietary supplementation (n-3 PUFA at a dose of 1.3 g twice daily for 3 weeks) and placebo administration on flow-mediated dilatation (FMD), pulse wave velocity, serum markers (NO, ADMA), lipid profile, and ΔVO2max were analysed in 13 cyclists both before and after dietary protocols. Significant differences between pre- and post-intervention baseline NO levels were observed after n-3 PUFA dietary protocol (13.9 ± 4.2 vs. 23.5 ± 3.6 µmol·l(-1); P < 0.001). Higher post-intervention baseline NO level was observed after n-3 PUFA diet compared with placebo (23.5 ± 3.6 vs. 15.3 ± 3.0 µmol·l(-1); P < 0.01, respectively). The n-3 PUFA increased baseline NO concentration (ΔNO) by 6.7 ± 3.8 µmol·l(-1) and placebo by 1.6 ± 4.4 µmol·l(-1). The positive correlation was observed between baseline post-intervention NO concentration and maximal oxygen uptake (r = 0.72; P < 0.01) and also between ΔNO and ΔVO2max (r = 0.54; P < 0.05) in response to omega-3 fatty acids supplementation. There was an association between a 5.25% higher FMD (P < 0.05) and higherΔVO2max (P < 0.001) after n-3 PUFA diet compared with lower values of placebo (r = 0.68; P < 0.05). These findings suggest that an increase in NO release in response to n-3 PUFA supplementation may play a central role in cardiovascular adaptive mechanisms and enhanced exercise performance in cyclists.

Introduction: Evaluation of effectiveness of pulmonary rehabilitation in patients with idiopathic pulmonary fibrosis (IPF) has not yet been presented in medical literature. The objective of the study is to analyze the influence of inspiratory muscle training on dyspnea (oxygen cost diagram [OCD], baseline dyspnea index [BDI]), quality of life (SF-36), results of 6 MWT (distance, dyspnea in Borg’s scale), maximal inspiratory pressure (MIP), and lung function tests (IC, TLC, VC, FEV1, DLCOSB, DLCO/VA) in patients with IPF. Material and methods: Investigations were conducted before, after 6 and 12 weeks of pulmonary rehabilitation performed in 2 groups of patients: study group (GB)—16 patients—with inspiratory muscle training added to general body conditioning and in control group (GK)—14 patients—who performed only general body conditioning. Results: After 12 weeks of rehabilitation in SG we noticed the significant decrease of dyspnoea before (p = 0.028) and after (p = 0.012) 6 MWT, increase of distance in 6 MWT (p = 0.001), increase of MIP (p = 0.006), decrease of dyspnoea in BDI (p = 0.001) and improvement of quality of life (SF-36/PCS; p = 0.030) in comparison to baseline values. In the GK we observed increase of distance in 6MWT (p = 0.001) and improvement in quality of life (SF-36/PCS; p = 0.016). No improvement in sensation of dyspnea during 6MWT, BDI and MIP was noticed in the GK. Conclusion: Adding inspiratory muscle training increases effectiveness of pulmonary rehabilitation in IPF patients.

Blood-Brain Barrier and Exercise – a Short Review Blood-brain barier (BBB) segregates central nervous system (CNS) from the circulating blood. BBB is formed by the brain capillary endothelial cells with complex tight junctions between them as well as by astrocytes and pericytes. BBB is responsible for transport of selected chemicals into and out of the CNS as well as for its protection from fluctuations in plasma composition following meals, during exercise and from circulating agents such as neurotransmitters, xenobiotics and other potentially harmful substances capable to disturb neural function. BBB may be compromised during CNS injury, infection, fever and in some nerodegenerative diseases. The increase of BBB permeability was observed also during exercise as documented by changes of plasma S-100 protein levels, used as a peripheral marker of BBB integrity. Marked change in BBB integrity during exercise may disturb normal brain function and contribute to the development of central fatigue. Moreover, serum S-100β may indicate level of injury in individuals suffering brain injuries during sports. There are also data suggesting that acute effect of physical exercise on serum S100β levels may not be related with CNS injury. Further studies to establish whether training and which type of it may modulate BBB permeability are needed.