Статьи журнала - Человек. Спорт. Медицина
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Neuronal mechanisms of the beneficial mood effects of physical excercise
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Aim. The current work aims to summarize the experimental data (from author’s and other laboratories) on the neuronal mechanism of the mood effect of physical exercise and to suggest a potential mood-stabilizing mechanism of physical activity. Materials and Methods. Physical Depression is a brain disorder characterized by severe emotional, cognitive, neuroendocrine, and somatic dysfunctions. Based on this concept, the author performed a review of experimental data on various ways to manage depression including medical treatment and physical exercise. Results. Although the last generation of antidepressant drugs demonstrates improved clinical efficacy and safety, the onset of their clinical effect is still significantly delayed from the beginning of the treatment course, and significant number of patients show lack of adequate response to these drugs and/or relapse of the disease even after initially successful treatment. Certain non-pharmaceutical strategies are used as adjuncts or replacements to antidepressant drugs when the formers are ineffective. One of such strategies is the voluntary physical exercise. Conclusions. Voluntary physical exercise can be an adjunct physiotherapeutic treatment in depression, given together with the pharmacotherapy, e.g., with SSRIs. One of the potential mechanisms of action of physical exercise in depression is stimulation of basic and/or reversal of the SSRI-induced inhibition of 5-HT tone. Other potential mechanisms, such as neuropeptide pathways, should be investigated in the future studies.
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Aim. The study aims to determine the normative values of the physical and motor skills in children aged 4-7 living in Turkey (Sakarya) based on age and gender, and to compare these data with the WHO data and with the literature of selected other countries. Materials and methods. The sample consisted of 777 primary schoolchildren (383 girls and 394 boys) aged 4-7 years. They were students at the “Private Şahin Schools” in the Sakarya province of Turkey. The height, weight, Body Mass Index, Body Fat Percentage, Standing Broad Jump, Straight Arm Hang, Agility Shuttle Run 10×5 meters, Sit and Reach, Plate Tapping, Flamingo Balance Floor Test, Flamingo Balance, Coordination Test, Sit Up, 20 Meters Shuttle Run, and Maximum Oxygen Intake VO2max tests were included in this study. In computing the average, standard deviation, and percentile values of the physical and motor values of the study group, the SPSS 22 Program was employed (frequencies and percentiles). Results. The results of each test determined the averages and normative values according to age and gender, together with 20 % groups for the anthropometric and psychomotor parameters of 4-7-year-old girls and boys. Also, a comparison was made with WHO data and the literature data of other countries. Conclusion. The current research determined the norms in the main motor and anthropometric skills for ages 4 to 7 based on age and gender in children living in Turkey (Sakarya province). The main motor and anthropometric skills play an important and necessary role in the proper and comprehensive development of a child. In this study, it was observed that there was no significant difference between the genders in anthropometric, psychomotor and functional characteristics in children aged 4-7 years.
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Optimal combination of training influences on the preparation of elite judokas in the annual cycle
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Aim. The paper is aimed at the elaboration and scientific argumentation of the optimum relationship between different components of elite judokas’ preparation during the annual training cycle. Materials and methods. The study was conducted in the national judo male team of the Republic of Moldova (n = 24, 18-25 years). The research was focused on the elaboration of experimental methods for judokas’ preparation during the annual training cycle by using physical, technical-tactical, competitive and recovery training. A pre-competitive training mezzo-cycle (MzC) was planned by distributing the effort parameters to 5 micro-cycles (MiC-s), calculating the mean, ±SD and the correlation between the indicators of training MiC-s by using the Spearman Rank Correlation nonparametric test. The detailed analysis of the annual training plan highlights its structure formed of three periods, 12 MzC-s, and the relationship between physical, technical - tactical and recovery training. Results. The results of the statistical calculations reveal (mean; ±SD) the number of days per MiC, namely 3.6 ± 0.89 days; total duration per MiC - 280.35 ± 35.1 min; total duration per training session - 80.77±17.3 min; total duration of general physical training (GPT) 24.51±10.1 min; and of special training (ST) - 45.3 ± 56.3 min. Effort ratio per MiC is 19.08 ± 2.5 %; GPT is 30.0 ± 9.9 %, ST -70.0 ± 9.9 % and the ST means - 129.34 ± 42.92 reps; RANDOURI and SHIAI - 10 ± 5.0 min. The characteristics of elite judokas’ pre-competitive training and the correlation of effort parameters in the pre-competitive period were also analyzed. Conclusion. The results reveal strong correlations between all the indicators of effort and training means in each MiC of elite judokas’ pre-competitive training, which confirms that the combination of different training components improves motor skills and technical-tactical mastery.
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Aim. To study the dynamics of the development of strength and speed-strength characteristics in men’s 800 m training during the winter macrocycle of running preparation. Material and methods. Four middle-distance athletes were included in the study. Seven indicators characterizing the strength- and speed-strength development were assessed during seven mesocycles of winter preparation. Results. The total strength reached its maximum volume in the first and second mesocycles. We tried to achieve a balance between the development of strength and endurance. Using special running exercises and short alternate leg bounds in the second and sixth mesocycles proved to have a forming input on special running preparation. The development of strength endurance takes place in the first three mesocycles. Conclusion. The strength and speed-strength training of 800 m runners has great importance for achieving high sports results. The effectiveness of the training process depends to a great extent on the structural distribution of strength preparation among the different mesocycles.
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Pedagogical concept of technical and tactical training of persons with disabilities in chess sport
Статья научная
Aim. The purpose of the study is to determine the systemic directions and priority ways and develop the stages and technologies for technical and tactical training of people with disabilities for achieving the effective results in chess sport in the long-time perspective. Materials and methods. The empirical study of technical and tactical training conducted in 2005-2015 involved 1275 persons at the age from 10 to 72 years with musculoskeletal disorders, hearing or visual impairments. The criteria for assessing the effectiveness of technical and tactical training were diagnostic questionnaires, specialized chess tests, as well as the following psychodiagnostic techniques: the Spielberger State-Trait Anxiety Inventory (STAI); well-being, activity, mood test (“SAN”-test); The Short Form-36; the UCLA Loneliness Scale. Results. The survey revealed the actual factors hindering effective sports training: difficulties in reaching the training sites, lack of information about chess sections and Internet availability. The upward trend in the technical and tactical training (TTT) dynamics is confirmed by the growth of results due to implementing strategy and tactics - up to 31 %; the development of operational thinking - up to 25 %; recent memory - up to 27 %, evaluative function - up to 31 %. As a result of sports training 72 chess players achieved the ranks and titles of The International Chess Federation, including the title of “International Chess Grand Master”. Conclusion. The pedagogical concept realized by a set of standard and innovative means, methods, organizational forms of adaptive TTT along with psychological and pedagogical support and comprehensive supervision allows to effectively transform the intellectual potential of a chess player into a sports result.
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Physical activity and sedentary behavior of university students on the Russian north
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The paper aims to analyze physical activity (PA) intensity levels and PA domains in Surgut State University (SSU) students in comparison with their EU peers on a gender- and age-specific basis. Results. Surgut State University students (n = 376, including 160 males and 216 females) of different ages participated in the study. It was found that PA averaged 1804 and 1707 МЕТ-min/week for male and female subsamples, respectively; the correlations were found between age and transportation PA (p = 0.0021), walking PA (p = 0.0021), total PA (p = 0.0253) for the female subsample; and between age and working PA (p = 0.0099), walking PA (p = 0.0278) and sedentary time (p = 0.001) for the male subsample. The gender-unspecific equations were obtained to rate the correlations between age and working PA (p = 0.0206), transportation PA (p = 0.0284), walking PA (p = 0.0001), total PA (p = 0.0086) and sedentary time (y = -3129 + 532x - 11.49x2 r = 0.1479; p = 0.0041). Furthermore, correlations were found between sedentary time and body mass indices for the male subsample (y = -3283 + 425x - - 7.23x2 r = 0.1578; p = 0.0463) and the gender-unspecific correlations for students’ domestic/gardening PA (y = 1153 - 46x + 0.45x2 r = -0.1321; p = 0.0103). The reported weekend sedentary time of SSU students was much higher than that of their peers from Poland, Czech Republic, Hungary and Slovakia, with the female subsample weekend sedentary time being higher than in the male subsample both in SSU students (p = 0.0015) and EU countries (p = 0.0000). Conclusion. On the whole the study data and analysis showed SSU students’ PA being inadequate for both gender groups.
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Introduction. Although the effect of the fat mass and obesity-associated (FTO) gene on adiposity is well established, there is a lack of evidence whether physical activity (PA) modifies the effect of FTO variants on obesity in Russians. Therefore, the purpose of this study was to examine PA influences and interactive effects between FTO variants and PA on measures of adiposity in Russians. Materials and methods. 110 Russian males aged 22-52 years old were examined. Anthropometry: height and weight, waist and hip circumferences were taken. The whole-body impedance was measured on the right-hand side of the body using the bioimpedance meter ABC-01 ‘Medas’ (SRC Medas, Russia) according to a conventional tetrapolar scheme at a frequency of 50 kHz. For each subject participating in the study, the genotype was determined by the polymorphic systems of the T/A (rs9939609) polymorphism of the FTO gene (Lytekh, Moscow). Results. Participants who did not engage in regular PA exhibited higher BMI, fat mass, HC, and WC with statistical significance (P ≤ 0.01). Although significant associations between the three FTO genotypes and adiposity measures were found in the sedentary group. There were no significant associations between FTO genotypes and obesity-related phenotypes in the PA group. Conclusion. Comparison of morphological parameters in carriers of alternative genotypes in two subgroups with different lifestyles makes it possible to conclude that the A allele determines a greater tendency to accumulate fat in cases where there is no regular physical activity.
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Physiological characteristics of strength component of special endurance in rugby players
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Aim. The purpose of the work was to identify the strength and special endurance of rugby players depending on their position. Materials and methods. In 2018-2019, the study involved 20 rugby players aged from 19 to 23 years. All athletes were divided into two functional groups of 10 people each (first group -forwards; second group - defenders). In both groups, special endurance and muscle strength were measured. Results. It was found that the strength measurements of the upper and lower extremities in the first group significantly exceeded the same parameter of the second group (14.7-31.03 %) (p
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Planning of effort parameters in the training of elite male judo athletes
Статья научная
Aim. The aim of this study was to evaluate the influence of effort parameters on the indicators of fitness tests according to the relation of the variables of training components in judo. Material and methods. Application of methods and basic directionality: repeated in series (adaptation), gradually repeated (optimum training state) and competitive (stereotypes). An experimental methodology of the specific training means was planned with 6 athletes monitored over 3 training mesocycles (MzC-s): basic, competitive 1 and competitive 2. The fitness tests checked the biological training (BT), physical training (PT), technical training (TT), technical and tactical training (T-TaT). The performances in two national competitions were also monitored. Parametric tests were conducted with a significance level of p ≤ 0.05. Results. The study results confirm the achievement of the training and performance objectives planned for each training MzC and the improvement of judokas’ BT, PT (16.67 % in basic and competitive MzC 1 and 12.63 % - competitive MzC 2), TT (41.66 % in basic MzC), tactical training (25 % in basic MzC) and T-TaT (66.66 % - competitive MzC 1 and 87.37 % - competitive MzC 2). The results of the correlative analysis between the 12 studied indicators reveal 24 significant correlations out of 91 correlations in the basic MzC (26.37 %), 26 correlations out of 91 in the competitive MzC 1 (28,57 %), and 24 correlations out of 78 in the competitive MzC 2 (30.77 %). Conclusion. These results show that the effort parameters influenced the judokas’ training improvement and the performance capacity increase.
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Статья научная
The aim of this study is to develop an adaptogenic drink based on the polyphenol complex of antioxidant activity optimized in terms of bioavailability. Materials and Methods. The study was performed on the base of the polyphenol complex of antioxidant activity made of taxifolin (Larix gmelinii extract with no less than 97.0 % of taxifolin) and plant extracts (Lonicera сaerulea L., Beta vulgaris L. ssp.vulgaris) obtained in the research laboratory of the department of Food and Biotechnologies in the South Ural State University. To increase solubility and bioavailability of taxifolin we used 20-minute 630 W ultrasonic impact, providing taxifolin nanostructuring. The plant extract consists of reconstituted extracts from Beta vulgaris L. ssp.vulgaris and Lonicera сaerulea L. in a 3:1 ratio with 0.1 % of taxifolin and the amount of dry substance of no less than 15 %. Taxifolin content in a final product is no less than 0.02 %. Results. It was established that taxifolin water solution is quite sensitive to ultrasonic cavitation. The morphological structure of taxifolin particles, treated with ultrasound, was close to a spherical shape. Particles were characterized by amorphous structure, which is positive for solubility and bioavailability properties. Antioxidant activity is 1.74-1.98 times higher than in the solutions obtained using a mechanical approach. This indicates the increased physiological value of solutions. The drink obtained on the base of beet and honeysuckle extracts with 0.1 % taxifolin had the total content of betanin and betaxanthine equaled 54 ± 2 mg/100 g and the total content of phenol substances of 194 ± 4 mg in terms of gallic acid. The consumption of a taxifolin plant extract-based drink results in the decrease of Streptococcus to significantly lower values. There is a shift in pH values in a range from 6.5 to 7.5 in comparison with the initial pH values of 5.5 ÷ 6.0 units. Conclusion. The combination of secondary metabolites (polyphenols) in the form of Lonicera сaerulea L. and Beta vulgaris L. ssp.vulgaris plant extracts with taxifolin is a very promising one for the technology of adaptogenic drinks to improve homeostatic mechanisms involving microbiota at the stage of oral intake.
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Aim. This study aimed to investigate PlayerLoad and heart rate responses of handball-based small-sided games which specifically designed with additional field player rule. Materials and Methods. Thirteen well-trained female handball players (2 goalkeepers, 2 pivots, 4 wings, and 5 backs) participated in this study. A total of eight Small-sided games (SSGs) on two different training days with separated at least 48-hour were conducted. SSGs executed with the inclusion of two each 5 vs 6 and 7 vs 6 handball specific games that mimic the numerical inferior or superior situations in game-play. PlayerLoad, acceleration, deceleration and change of direction were established by a wearable IMUs and heart rate monitored with a chest band. Results. There was no significant difference between PlayerLoadtotal, PlayerLoadmin-1, HRmax, HRavr, and HIE parameters during the SSGs that separated by two testing days. No significant differences were found in PlayerLoadtotal, PlayerLoadmin-1, HRmax, and HRavr, parameters attained from the main and opponent team. Results showed no significant differences between all 5 vs 6 and 7 vs 6 SSGs. There was a significantly lower PlayerLoadtotal in the goalkeepers than backs, wings and pivots. The mean and maximum heart rate of back players was significantly lower than wings and pivots. Conclusion. Current study set out the examiner that if tactical innovations in playing situations numerical inferiority or superiority situations 7vs6 and 5vs6, will make the difference in players’ physical efforts. Because of the raised usage of this tactical variations, recent studies only focused to technical variables of playing with no goalkeeper and additional field player. Therefore, it is crucial to obtain clear knowledge how to affect the players as physically. Hence, a definite need for revision of the training demands of the goalkeepers in handball.
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Possibilities of regulating antioxidant activity of medicinal plant extracts
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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
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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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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
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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
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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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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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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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