Статьи журнала - Человек. Спорт. Медицина
Все статьи: 2648
Possibilities of regulating antioxidant activity of medicinal plant extracts
Статья научная
The aim of the paper. The aim of the present paper is to evaluate the effectiveness of extracting biologically active substances of antioxidant action from plant raw materials on the basis of applying different extraction approaches. Materials and methods. We did the chemical research of BAS extracts Lonicera сaerulea L. and Urtica folia L. concerning their migration parameters during fraction division (honeysuckle berries) and changing extraction conditions (dried nettle leaves). Freeze-drying of raw material (by means of a freeze-drying apparatus “Ineye-6” under the following conditions: temperature -50 ± 5 °C, pressure no more than 6 Pa) was applied to preserve the bioactivity in a honeysuckle fraction. The experiment included a wide range of chemical parameters - antioxidant activity (АОА), mass fraction of extractives, phenol compounds, anthocyanins and vitamins. The UFLC Shimadzu Corporation Pump: LC-20AD Detector: SPD-M20A Prominence Diode array detector was used to identify bioactive substances. Results and discussion. The paper studies the influence of various approaches concerning bioactive compounds extraction from Lonicera сaerulea L. and Urtica folia L. The application of ultrasound (US) with frequencies 22 ± 0.6 kHz increases the effectiveness of extraction process. It helps to conduct extraction at low temperatures (60 ± 2 °С) without using chemical reagents. The paper presents the results of water and ethanol extraction obtained from different fractions of honeysuckle and dried nettle leaves. It also provides the results of antioxidant activity analysis of this extraction and a total of antioxidant activity. Urtica folia L extracted by US of 120 W (2,4043 ± 0,084 mg/ml) and a sample based on the water-ethanol extraction agent without an ultrasonic bath (2,5209 ± 0,032 mg/ml) showed higher antioxidant activity. We defined the technological parameters of obtaining a dry extract of Lonicera сaerulea L by means of ultrasound and freeze-drying for preserving the maximum bioactive compounds of raw material (up to 92-85 %). Conclusion. The results of the experiment proved that ultrasound-assisted extraction improves the extraction kinetics and the output of bioactive compounds from the substrate. The extraction technology excludes the infusion stage which reduces energy intensity.
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Post-COVID-19 period of prejudices - the invisible burden of tourism
Статья научная
Aim. After two and a half years of the strong impact of the pandemic on society and the economy, it seems that there are still negative consequences. The goal of the research was to determine which type of fear has the greatest impact on tourists' awareness of the intention to travel to countries that have had the strongest negative impact from the pandemic, and which, thanks to prejudice, have been marked as “risky”.
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Postural imbalance is accompanied by changes in cardiac rhythm and conduction in young athletes
Статья научная
Aim. The aim of the study was to identify the correlation between postural balance and changes in cardiac rhythm and conduction in athletes ages 16-18. Materials and methods. The study involved 266 male athletes (training experience - 6-10 years, representatives of 5 sports, namely athletics, swimming, speed skating, cross-country skiing, wrestling) in the recovery period. For each subject a 12-lead ECG recording was obtained (rest, PWC170 test, 5-minute recovery) and force platform data (2 tests with open and closed eyes) were collected. Results. It was found that 50.38% of athletes have changes in rhythm and conduction, namely incomplete right bundle branch block (IRBBB), extrasystole, early repolarization (ER), sinoatrial (SA) block (1st degree) and pacemaker migration. After examination all athletes were divided into 2 groups: 1 - no ECG changes (n = 132); 0 - ECG changes (n = 134). It was found that analyzing ECG data without dividing by sport did not allow us to establish differences in postural balance, which was associated with a high variability of the maximum and minimum individual values. Conclusion. The subsequent analysis of force platform data was performed based on sports disciplines, and it showed significant differences between the groups of athletes. The data obtained confirm the correlation between postural balance and ECG. These differences were determined by specific patterns of motor actions, which activated compensatory mechanisms resulting in the development of rhythm and conduction disturbances.
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Статья научная
Aim. Investigate the predictive relationship between 100 m front crawl swimming performance of youth swimmers and anthropometric characteristics. Materials and methods. Fifty-one active athletes (n = 30 male and n = 21 female) participated in the research and for the purposes of the analysis were divided into two categories (13-15 years n = 32, and 16-18 years old, n = 19). The following anthropometric data were used as set of predictive variables (7 longitudinal, 7 skinfolds, 3 circumference and 1 voluminosity variables). Results. One prediction model for each gender and age group emerged. The percentage of the explained variance of the dependent variable (100 m front crawl performance time) is 84.6 %, 54.4 %, 71.1 % and 72.7 % respectively for male, female, youth and cadet swimmers. The significant variables for each model were: arm span, biceps skinfold, biceps bracchi circumference in contraction for male swimmers, sitting height for female swimmers, biceps bracchi circumference in contraction and body weight for youth swimmers, triceps skinfold and biceps bracchi circumference in contraction for cadet swimmers. Conclusion. Youth swimmers’ performance can be predicted by important anthropometric parameters.
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Prospects for the application of taxifolin based nanoemulsions as a part of sport nutrition products
Статья научная
Aim. The article deals with the analysis of the effect of sport nutrition products enriched by taxifolin encapsulated into nanoemulsion on people involved in low-intensity sports for forecasting changes in homeostasis. Materials and methods. 3 groups of volunteers aged 25-35 (n = 30) and involved in sports on a regular basis (low-intensity training, 2 times per week) participated in a placebo-controlled study. The extract and nanoemulsion of taxifolin were used as antioxidants. To estimate the effect of enriched products on homeostasis, we performed a non-invasive study of hematological and biochemical indicators. Results. This paper demonstrates the results of the study of oil-water emulsions obtained with ultrasonic treatment for the encapsulation of biologically active substance - taxifolin - to improve and preserve its bioactive properties. We conducted an analysis of metabolism after the inclusion of taxifolin-enriched products in a diet. We established that the inclusion of taxifolin-enriched products does not result in worsening of lipid, carbohydrate, and protein metabolism. Conclusion. The paper demonstrates the reason for the inclusion of products enriched with taxifolin encapsulated into nanoemulsion in the diet of people involved in low-intensity sports for minimizing the risk of oxidative stress and providing homeostasis regulation.
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Psychological condition and postural muscle imbalances in skiers
Статья научная
The aim: to identify the relationship between the musculoskeletal system and Central nervous system. The study involved 20 skiers from the South Ural State University team (10 males, 10 females) aged 18-21. Each participant underwent a stabilometric evaluation for potential spinal deformity and psychological profiling. The parameters describing the spinal deformity revealed specific individual postural features and allowed clarifying the cause of observed deviations in the vertical body posture. Psychological tests showed the psycho-emotional state of athletes. The present research findings show that individual physiological and psychological profiling of athletes is essential for improvement of their sports’ performance as well as for defining optimal diagnostic and physio- and psycho-therapeutic procedures.
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Psychophysiological status in overweight individuals
Статья научная
Aim. The article deals with establishing psychophysiological features in overweight women to develop a set of measures for weight decrease and psychocorrection. Materials and methods. We studied two groups of women who were willing to participate in the study: the first group - mean age 54.2 ± 3.0; the second group - mean age 25.0 ± 1.7. The average BMI of the first group corresponded with obesity values (32.3 ± 1.6), while an average BMI of the second group was within the upper limit of reference values (23.7 ± 0.9). However, according to body composition data, there was a risk of BMI increase. As far as the percentage of adipose tissue exceeded the recommended values, recommended weight loss was 18.2 ± 2.6 kg for the older group and 5.6 ± 1.4 kg for the young group. Two groups of women of the same age with normal weight were examined as control groups. Results of the study revealed both age-related and psychophysiological features in women of different weight. EEG analysis showed that alpha rhythm amplitude in women from the first group was higher on average and frequency was lower compared to the second group. In the experimental group, we also revealed a higher level of delta activity in the frontal region at rest. The study of a psychoemotional status revealed that all participants hardly coped with stress. However, young participants overcame stress more easily compared to the older group. Anxiety assessment showed increased values of anxiety. In all participants, personal anxiety was almost at the same level within 48 points. Situational anxiety was higher in young women (51.2 ± 1.3 and 49.6 ± 2.1 points, respectively). Conclusion. The most psychophysiological indicators identified functional stress, particularly in overweight older women. To preserve the optimal psychophysiological status of persons participating in weight correction programs, it is also necessary to correct a psychophysical status in accordance with age-related features.
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Pulmonary adaptation and unknown breathing issues in athletes with disabilities
Статья научная
Aim. This study aimed to assess baseline pulmonary function and long-term respiratory adaptations to exercise and athletic training across various groups of para-athletes. Materials and methods. Two hundred thirty-two athletes (aged 6–60 years) with varying disabilities and representing different sports disciplines underwent anthropometric and respiratory function assessments. Results. Key findings included: (i) near-normal average relative vital capacity (95–100%) was observed only in athletes engaged in orienteering, para swimming, and para cross-country skiing, whereas most participants exhibited suboptimal respiratory function relative to individual normative values; (ii) wide data ranges (min-max) indicated significant intra-group heterogeneity. Conclusion. Pulmonary function evaluation is crucial for a comprehensive assessment of athletic performance in para-athletes, with important implications for optimizing exercise interventions and training regimen management.
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Статья научная
Aim. The research was conducted with the primary aim of determining the antropometric characteristics as well as motor and functional abilities of three groups of examinees over a two-year period of organized physical activity engagement. The secondary aims were to examine each group's nutritional status and their connection to the results achieved in the functional ability evaluation. Material and methods. In the total sample which consisted of 147 pupils, one group was engaged in martial arts (karate, wrestling, taekwondo and kick-boxing), the second group in team sports played with a ball (football, handball and basketball), while the third group was physically active only on Physical Education classes. Ten variables were used for the needs of the research, while to process the data, the Student's t-test for dependable samples, the discriminant analysis and the correlation analysis were used. Results. For all the three measurements, the results show the superiority of examinees - athletes compared to non-athletes. Engaging in team sports played with a ball at the age of 11 to 13 has a more positive influence on the analysed variables of the anthropological status than for peers who are non-athletes, but the same was not shown for athletes engaging in martial arts (p
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Статья научная
Aim. Forearm extension and radio-ulnar pronation are two common components of the final movement during each badminton smash stroke. By coordinating the forearm to produce both extension and pronation at the same time, racket head velocity can be increased. Thus, this study examined maximal velocity and racket deflection during both movements in regard with skill level. Materials and methods. Twenty-two players (8 experts and 14 novices) participated in this study. Wrist, handle and racket head velocity were recorded using high speed cameras (Vicon V8i at a frequency of 250 Hz). Results. The racket head velocity with radio-ulnar pronation was 16 % higher than with forearm extension. This higher velocity resulted from an 8 % higher acceleration and a 70 % higher maximal angular velocity of the end points of the forearm segments during radio-ulnar pronation. In each movement, experts’ maximal velocity was higher than that of novices (p
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Статья научная
Aim. The article deals with establishing the effect of food, enriched with antioxidants, on people, practicing low-intensity sports, to forecast changes in homeostasis. Materials and methods. We used the data obtained from participants aged 25-35 (40 persons), practicing low intensity sports on a regular basis twice a week. As antioxidants, we used micronized taxifolin (0.58 % to product mass), chaga extract (5.76 % to product mass), and fucoidan (0.5 % to product mass). To assess the effect of enriched products on homeostasis, we performed the study of hematological and biochemical indicators with the help of non-contact blood analyzer. Results. We performed the analysis of metabolism after adding in a person’s diet the products, enriched with biologically active substances. We also wanted to study the metabolic effect of changing a person’s diet. We established that, in general, the inclusion into a person’s diet of antioxidant enriched products do not result in a decrease of lipid and carbohydrate metabolism. However, antioxidant enriched products have a multidirectional influence on carbohydrate and lipid metabolism and enzymatic activity. From the prognostic point of view, there is a minimization of the risks of oxidative stress after the inclusion of food products, enriched with micronized taxifolin, into the diet of athletes from low-intensity sports. In comparison with other groups, there are no changes in the concentration of acetylcholinesterase (248.70 ± 2.4 umol/l; reference values 220-278 umol/l) after the decrease of amylase concentration. Conclusion. Homeostatic regulation is provided by the inclusion of specialized foods, which minimize the risks of oxidative stress, into a diet of athletes, involved in low-intensity sports.
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Статья обзорная
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Статья научная
Aim. The objectives of this research are to analyse the ways how a child spends time with his/her family as well as the child's developmental risks of obesity and risk behaviours in the kindergarten and to determine whether the different ways of spending time with the family are connected to the two types of developmental risks in children (risk behaviours in the kindergarten and the risk of obesity in children). Materials and methods. With a sample of 122 participants aged 3-5 years from the city of Rijeka and its surroundings, a survey questionnaire was used to assess how children spend their time with their parents when they are not attending the kindergarten and how much time they spend walking, riding a bicycle, swimming, playing on the computer, or watching television and what their body mass index and risk of obesity index are. The second part of the questionnaire was filled out by the preschool teachers and it assessed children's externalized and internalized risk behaviours in accordance with the SCBE Scale. Results. The obtained results indicate that the older the child, the more time he/she spends on the computer. The analysis of sex differences found only that girls spend more time swimming than boys. There are some weak but significant links between the length of time a child spends watching media content while with the family and risk behaviours in the kindergarten and other developmental risks such as obesity. Conclusion. However, additional research is needed to determine the applicability of the results in preventing unfavourable child development.
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Авторы, опираясь на международный научно-практический опыт, делают заключение о необходимости создания и развития в системе здравоохранения России STAT-лабораторий. Высказывается экспериментально-обоснованное мнение о том, что эффективная работа STAT-лабораторий возможна только при широком взаимодействии разных служб медицинских центров при условии самой широкой интеграции медицины и образования, науки, техники и технологий, подготовки качественно новых специалистов по новым специальностям.
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Scientific and theoretical aspects of intellectual training in game sports
Статья научная
Aim. This paper provides an experimental foundation for the scientific and theoretical aspects of intellectual training in game sports.
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Selenium as a factor for maintaining physical performance in elite athletes
Статья научная
Aim. The aim of this study was to identify the effect of selenium on physical performance in elite athletes during control and preparatory training mesocycles. Materials and methods. This research involved 44 highly skilled male track and field athletes aged 19.9 ± 0.21 years; 20 athletes were included in the control group. Athletes in the experimental group (12 athletes) took the selenium-containing supplement at a 50 µg selenium dose per day for 21 days of intensive training loads; the same number of athletes made up the no-treatment group. The control group was examined once, while the experimental and no-treatment groups were examined twice: at the beginning of the study and after 21 days of intensive training. Heart rate was recorded, blood pressure was measured, and the heart rate variability parameters and overall physical performance were determined by the PWC170 test. Results. The results of the PWC170 test increased 1.22 times (P
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Sex differentiation of morphological characteristics and motor skills in preschool-aged children
Статья научная
Aim. The research was conducted with the aim of determining preschool-aged children’s sex differentiation using the multivariate and univariate variance analyses (MANOVA/ANOVA). Material and methods. A battery of measuring instruments comprising 17 variables (8 morphological characteristics variables and 9 motor skills variables) was carried out on a sample of 69 children (49 boys and 20 girls), aged 5 and 6, from the Primorje-Gorski Kotar County in the Republic of Croatia. Results. The results showed that, between boys and girls of this age, there are multivariate statistically significant differences in arithmetic meanings at the level of p =.022 in the entire system of morphological and motor variables, whereas univariate values did not show a statistical significance. Conclusion. The conclusion is drawn that in the morphologic space in children between the ages of five and six years, there are quite equal developmental processes based on sex differentiation and genetic determinations (4:4); however, this is more pronounced in the motor space in favor of the girls (2:7) at this age.
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Short-term diet modification can moderate the levels of fatigue indices in tennis players
Статья научная
Aim. The Objective of this study was to investigate the effect of short-term diet modification on plasma levels of fatigue indices (including serotonin, dopamine, serotonin/dopamine ratio, ammonia, and lactate) following a two-hour tennis match. Materials and methods. 32 semi-professional male tennis players participated in a randomized cross-over design in the form of short-term diet modification (DM) and non-modification (N-DM) interventions. They played a formal two-hour match and plasma levels of fatigue indices and RPE scores of participants were determined before and after each tennis match. Results. The results of this study showed that after the match, the serotonin, dopamine, lactate, and ammonia increased significantly compared to pre-match in both interventions (p
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Статья научная
Aim. The aim of this study is to overcome the problem of nutrient bioavailability in drinks for athletes, which is the result of their low permeability in metabolic processes of the body. For this purpose, we used sonochemical micronization of taxifolin - the most effective antioxidant. Materials and methods. To improve taxifolin solubility and bioavailability we used ultrasound treatment, which allowed us to provide taxifolin micronization on the following conditions: 5-, 15- and 25-minute treatment of 20 ± 2 kHz with radiation intensity of at least 10 W/cm2, power of 170, 400 and 630 W and temperature within 50 °С. The study was conducted using the following methods: microstructural analysis of native taxifolin and its solutions, including those obtained with sonochemical micronization; analysis of the disperse composition of taxifolin solutions; assessment of the total antioxidant activity of these solutions; assessment of taxifolin solubility and colloidal stability of its solutions. Results. We established that sonochemical micronization allows us to obtain solutions with the predominance of particles of no more than 100 nm. The morphological structure of taxifolin particles has significantly changed, particles are characterized by more homogenous and amorphous structure. We noticed some decrease in antioxidant activity under increased ultrasound exposure. Optimization of ultrasound exposure with the controlling parameter “average particle size” allowed us to establish the most effective mode (600 W, 18 minutes), which helped us to improve the colloidal stability of taxifolin solution and taxifolin solubility 6 times in comparison with the control sample. Conclusion. Sonochemical micronization should be regarded as convenient for the development of a new form of taxifolin with increased solubility and bioavailability, which can be used for the production of drinks for athletes.
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Possibility is investigated to enhance spatial resolution of diffuse optical tomograms reconstructed by the photon average trajectories (PAT) method. The PAT method is based on a concept of average statistical trajectory of light energy transfer from point source to point detector. The inverse problem of diffuse optical tomography reduces to solution of an integral equation with integration by conventional PAT. In the result for reconstruction of diffuse optical images the conventional algorithms of projection tomography can be applied, including filtered backprojection algorithm. The shortcoming of the PAT method is that it reconstructs I mages blurred in the result of averaging by photons spatial distribution contributing into the signal measured by a detector. To enhance resolution we apply a spatially variant blur model based on interpolation of spatially invariant point spread functions simulated for different image regions. To restore tomograms two iterative algorithms for solution of system of linear algebraic equations are used: conjugate gradient algorithm for least squares problems and modified residual norm steepest descent algorithm. It is shown that one can achieve 30% enhancement of spatial resolution.
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