The movement dynamic characteristics are the main parameters for physical exercise dosing during the athlete recovery process. However, taking into account the geometric characteristics of movement is no less important, especially when restoring the joint range of motion. The hypothesis of the study was the assumption that the use of movements’ geometric characteristics allows to “design” the optimal physiological rehabilitation patterns for movement volume restoration. Objective: to develop general principles and to create a mathematical model of the optimal trajectory characteristics for the restored part of the athlete’s musculoskeletal system. Materials and methods: We used 3D Qualisys Motion Capture and Analysis System in our investigation. The study involved 32 complex coordination sports athletes (age 9-15) with hip and ankle joint injuries (bruises, sprains strains). All they required a joint movement volume restoration. Results: The study revealed that joint movement volume restoration following the individually selected pathways involving effective mathematical modeling (study group) takes shorter time to restore the athletes than traditional physiotherapy methods (control group). For typical injuries (bruises, sprains and strains) of the hip joint area, the rehabilitation took 18±5 days for controls and 12±3 days for experimental group subjects. Nearly the same pattern was observed in restoration the ankle joint (12±4 days of recovery for controls versus 8±3 days for the experimental group). Conclusions: Restoring the joint movement volume, the workloads should be evaluated with geometric rather than dynamic indicators; for planar movement, that should be the distal limb path curvature relative to the restored joint.

The Olympic Games are a mega-event not only for athletes, coaches and referees. It is also very important for all citizens of the Olympic Games host country. The Olympics legacy is the development of mass rather than professional sport. Six years passed since Sochi Olympics and now it is time to evaluate and analyze the intangible aspect of the mega-sports event legacy. We analyzed the data on the overall growth in the number of people systematically involved in physical education and sports in Russia from 2008 to 2019. The study findings suggest a significant positive impact of the Olympics on people’s lifestyle. Over the decade, the number of people involved in physical education and sports in Russia increased 2.5 times. The main positive effect is revealed in young people.

Objective: to study the morphological and functional features of young athletes. Materials and methods: The study involved 102 young athletes aged 12 to 17. The control (0) group included 28 schoolchildren who were not involved in professional sport. The study group (1) included 35 children from a youth sport swimming school. The study group (2) included 47 young field hockey players. The study group (3) included 20 young athletes from the Republican Specialized Children and Youth Sports School of the Olympic Fencing Reserve of the Republic of Tatarstan. The examination of the children involved: anamnestic data, a survey, a general clinical examination, a blood pressure measurement, dynamometry, anthropometry (measurement of weight and height with body mass index calculation), body composition analysis with a TANITA analyzer. All the young athletes were examined by specialists: a cardiologist, a neurologist, a surgeon, an orthopedist, an ophthalmologist, an otorhinolaryngologist and a dentist. The laboratory and instrumental tests included: a clinical blood test, a general urine test, a resting ECG and a cardiac stress test, an echocardiogram, a respiratory function test, an ultrasound abdominal cavity and pelvic organs test. Results: the young athletes demonstrated higher physical development parameters than the average values in the control group. The percentage of the body fat in the boys and girls in the control group is significantly higher than that in the young athletes. At the same time, the muscle mass in boys not involved in sports is lower than the that in the groups of athletes. Findings: The study, the screening and the retrospective analysis revealed significant differences in the characteristics of the studied groups of children and adolescents, as well as the presence of individual conditions associated with sports.

Objective: to assess with exercise tests the endothelial dysfunction (ED) and performance before and after the treatment with specialized athlete’s nutrition product (SANP) with apian and herbal components. Materials and methods: 88 athletes aged 16-18 we tested. The main group included 58 athletes, who took SANP (candy bar «Gold F25 ApiSpeis Light») for 2 months. The control group-1 included 32 schoolchildren and students, non-athletes, with normal endothelium-dependent vasodilatation function of the brachial artery (EDVD BA) at the peak of the reactive hyperemia test (RHT). Control group-2, 30 athletes who did not take SANP, was formed for the comparison with the main group after taking SANP. For all individuals, we evaluated the level of EDVD, endothelium-dependent vasoconstriction (EDVC BA) at the peak of the hyperventilation test (HVT), the coefficients (C) of the endothelial sensitivity to shear stress and the blood flow velocity (Vps) of the BA at the peak of the RHT and HVT, the endothelial sensitivity index (ESI), and the maximum load (Wmax), the anaerobic threshold time (ATT). We also did general and biochemical blood tests. Results: the earliest manifestation of endothelial dysfunction is a decrease in sensitivity to shear stress during RHT and HVT resulting from endotheliocyte overstrain which can be assessed with ESI (sensitivity 80.9%, specificity 99.4 The EDVD diagnostic significance was 5.6 times lower than that of EIS, while 10.5% of athletes with over 10% EDVD actually had ED, with a predominant vasospasm and high cardiovascular risk. After the course of SANP in the main group, EDVD increased by 70%, EDVC decreased by 2.2 times, and the ESI increased by 2.3 times, against the background of improved performance. Total cholesterol decreased by 13%, triglycerides by 17%, cortisol by 14%, lactate by 25%. Red blood cell and mineral levels increased. A correlation was found between an increase in ATT a decrease in cortisol (r=-0.53; p<0.0001), an increase in red blood cells (r=0.62; p<0.0001), and an increase in Vps in BA during of hyperventilation with an increase in Wmax (r=0.52; p<0.0001). Conclusions: ED is the main factor of cardiovascular risk, limiting working capacity and forming a spastic type of regional hemodynamics of young athletes. The ESI criterion enables the detection of a decrease in the endothelial sensitivity to shear stress during
a hyperventilation test, which causes the predominant vasospasm. Th e tested SANP can be used in the system of biomedical support for young athletes.

Even the most experienced athletes are not safe from various types of muscle damage (cramp, contracture, sprain, tear and tear of the muscle). Nowadays, certain gene variations or polymorphisms associated with muscle damage caused by exercise are known. This review focuses on the polymorphism of the ACTN3 gene (Alpha-actinin-3 R577X, rs1815739), which plays an important role in the initial phase of muscle damage caused by exercises. Knowledge about how someone can respond to a specific type of exercises can help coaches individualize their athletes’ training exercises and thereby reduce the risk of injuries associated with overexertion. The purpose of this review is to provide a critical analysis of the literature on ACTN3 gene polymorphism associated with exercise-induced muscle damage both in young and old people, and the review highlights the potential mechanisms underlying these associations, which will provide a better understanding of exercise-induced muscle damage.

Objective: to determine the value of the body mass index (BMI) in cardiovascular patients for the sudden cardiac death (SCD) prediction. Materials and methods: we analyzed the medical archives of: 1) the Federal Research Clinical Center for Specialized Types of Healthcare and Medical Technologies, the Federal Biomedical Agency of Russia (comparison group I). The study included young athletes (N=603) without cardiovascular pathology, as well as those with cardiovascular diseases diagnosed in a medical examination; 2) Thanatological Department of the Bureau of Forensic Medical Examination (comparison group II). The sample (N=30) is represented by coronary heart disease (CHD) associated SCD cases; 3) the cardiac surgery Department of the Hospital of Emergency Medical Service (comparison group III). The sample (N=81) is represented by acute coronary syndrome (ACS) cases; 4) the cardiac surgery Department of the Clinic of Rostov State Medical University (comparison group IV). The sample (N=95) is represented by CHD patients who were on routine treatment. We calculated BMI in each comparison group. Results: in comparison group I, the BMI was 22.10±1.67 kg/m², in group II-18.7±0.45 kg/m², in group III – 28.01±0.58 kg/m², in group IV – 28.66±0.47 kg/m². The calculated value of χ² both for all groups and for their pairwise comparison was statistically significant (p<0.01), which suggests that there is a close association of obesity with an increased risk of CHD. Conclusions: the relationship between BMI and the presence of cardiovascular pathology in I comparison group (athletes) was not established. For groups II – IV, BMI is in a statistically significant association with cardiovascular pathology.

The article presents the modern data of from national and foreign literature on the problems associated with the influence of the type and intensity of physical activity on the state of red blood cells, both in athletes and in untrained subjects. The article emphasizes the role of intensive training in the damage to the erythrocyte membrane and describes the possible mechanisms of these disorders in athletes of different sports, as well as ways to restore them. The article dwells upon the possibilities to correct red blood cell disorders in various pathologies with physical exercises.

The literature review discusses current trends in the isokinetic machines (IM) use for both training and diagnostic purposes. The review dwells upon a wide range of IM applications, testing and training results, and demonstrates the applied nature of the IM use. The review addresses the issues IM use in professional sports. We come to the conclusion about a wide range of IM applications in both research and clinical practice. Despite IM disadvantages (high cost, necessity of special staff training, test results variability depending on an IM model), IM is a powerful tool in a health care professional’s arsenal which provides a qualitative improvement of clinical practice.

Objective: to study the objective and subjective parameters of the functional “cost” of technical and tactical activities (TRIMP, standard units, RPE, score) and compare them with the expert assessment of technical and tactical readiness of young professional football players (EXPERT, score). Materials and methods: 30 students of the professional football academy (mean age 16.4±1.2 years) were tested with Polar Team Pro sports technology from Polar (Finland). The professional football coaches (n=6, license A-C) after each official game scored (from 1-10).an expert assessment of the implementation of the players technical and tactical readiness. Results: a linear relationship between the physiological indicator “training impulse” (TRIMP) and the expert assessment of coaches of technical and tactical readiness were found. Were revealed that RPE subjective information from athletes-players is a convenient express method of receiving feedback, but it does not demonstrate a high correlation with technical and tactical readiness. The variance analysis found a decrease in functional costs in official matches relative to training sessions. Conclusion: the combined monitoring of subjective (RPE) and objective (TRIMP) parameters of functional “cost” is the most effective in practice.

Objective: to study heart rate variability in university students engaged in competitive sports at the beginning of a training season. Materials and Methods: the study summarizes the results of 141 participants. The study group consisted of 61 athletes (22.7±1.3 years), 31 men (22.3±1.3 years) and 30 women (23.1±2.1 years). The control group included 80 students not involved in sports (23.6±1.5 years), 34 men (23.7±1.5 years) and 46 women (23.6±1.5 years). Heart rate variability was assessed by a cardiointervalogramm registration in the background recording of rest for 5 minutes, as well as during an active orthostatic test. A spectral analysis of heart rate wave structure included registration HF, LF, VLF-components, LF/HF ration, and the total power of all waves – TP; complex indices were determined, namely the index of vegetative balance (AMO/SD index) and C30:15 coefficient. Results: we found higher level total spectrum power, parasympathetic activity and reactivity regulation in the study group. We revealed higher spectral indices, as well as C30:15 during active orthostatic tests in the group of athletes. HRV indices of male athletes are higher, both at rest and in orthostasis. HRV indices of female athletes significantly differed only in orthostasis, demonstrating a higher level of regulation. Conclusions: at the beginning of a training season, we found high level of regulatory indices in the functional state of competitive athletes, both male and female. A variety of significant differences in HRV in the studied groups can be used for a dynamic monitoring of changes in regulatory processes during the training cycle.