Ekologiya cheloveka (Human Ecology)

BACKGROUND: Adaptive responses to harsh environmental conditions of the Arctic may vary not only among adults, but also among children and adolescents. These compensatory reactions are influenced by the predominant type of regulation of the autonomic nervous system. The myocardium and its electrical properties play a significant role in determining how individuals adapt to to environmental conditions.

AIM: To study correlations between PP and TR intervals in adolescents in adolescents undergoing the clinostatic test and the Martinet test during the winter season.

MATERIAL AND METHODS: Twenty cardiac cycles were recorded in 22 adolescents aged 15–16 years in the II standard lead, both at baseline and after conducting the clinostatic and Martinet tests. Durations of the RR and TR intervals were measured and used for the analysis. Statistical processing of the data was performed using the MS Excel tables.

RESULTS: Based on both individual and group data analysis, it has been observed that the duration of RR and TR increases during the clinostatic test, while it decreases during the Martinet test. The extent of these changes in RR and TR varies between the two tests. Specifically, the RR:TR ratios are 1:3.5 during the clinostatic test and 1:2.5 during the Martinet test. These findings suggest a higher likelihood of parasympathetic influences on the electrical properties of the myocardium during the clinostatic test, and sympathetic influences during the Martinet test.

CONCLUSION: Duration of RR and TR intervals increased by 25% and 85%, respectively, in response to the clinostatic test. Conversely, after the Martinet test, the duration of both intervals decreased by 15% and 38%, respectively. These findings suggest that the changes in the duration of RR and TR intervals are influenced by the parasympathetic and sympathetic divisions of the autonomic nervous system, under different types of physical stress. Further research should be conducted in other seasons, particularly during transitional periods such as spring and autumn, to better understand the electrical properties of the myocardium under physical stress.

BACKGROUND: In today's society, there is a need to explore strategies for attaining and improving overall well-being. This exploration requires an examination of perceptions of well-being in different social groups. First and second-year students in higher education institutions represent the future social capital of the nation. Understanding the factors that contribute to their sense of well-being is essential, as it can determine their future social interactions and behaviors.

AIM: to identify the content of students’ perceptions of well-being.

MATERIAL AND METHODS: The study included 258 first- and second-year university students. The main research method was a modified free association technique, where students were asked to provide three associations in the form of verbs, adjectives, and nouns, resulting in a total of nine associations per participant. Data were analyzed using frequency analysis and calculation of ranks.

RESULTS: A total of 2322 associations were identified among students. These associations were then organized to form 51 associative groups, which were further combined into 16 semantic groups for meaningful interpretation. The concept of "well-being" was analyzed within a structured semantic space, focusing on emotional and motivational-need characteristics. The semantic space of the concept of “well-being” is structured according to emotional and motivational-need characteristics. The emotional component of well-being encompasses a range of positive emotions with varying degrees of intensity. On the other hand, the motivational-need component primarily addressed needs related to physical comfort, safety, basic life support, and material support.

CONCLUSION: In the content of university students’ perceptions about well-being, the emotional sphere holds the most significant position. Students associate well-being with feelings of calm joy, happiness and emotional stability. Additionally, perceptions of well-being are centered around fulfilling basic and material needs.

BACKGROUND: Adaptation of human body to the harsh conditions of the European North remains a topic of ongoing interest, despite numerous studies on the subject. There is a need to study population groups whose daily activities involve physical activity in extreme northern conditions. One such group includes athletes who participate in endurance sports. For athletes engaged in cyclical sports, competitive activities becomes can be particularly demanding, requiring sustained physical exertion and maximum power generation. Training and competing in harsh conditions place significant strain on the body’s cardiovascular regulation mechanisms. Over time, this may result in detrimental structural and biochemical changes in the cardiovascular system.

AIM: To identify the patterns of changes in heart rate regulation among track and field athletes and skiers after a training load.

MATERIAL AND METHODS: Athletes from the Arkhangelsk region, including skiers and track and field athletes in the mass sports categories, who regularly compete in regional events, took part in the study. The studies took place in the medical offices of sports complexes, where the UPFT-1/30“Psychophysiologist” device was used to record and analyze cardiointervalograms. Blood pressure was recorded before and after training sessions using the Criticare System 8100H monitor.

RESULTS: The initial variational span (VR) values of the duration of cardio intervals before exercise were slightly lower than the reference values in both the group of skiers and the group of athletes. At the same time, the mean square deviation (SD) values initially fell within normal range. Following the training load, both groups experienced a statistically significant decrease in SD and VR values, falling below the lower limit of the permissible range. Furthermore, spectral analysis of the cardiac intervals before exercise indicated a high level of neurohumoral regulation. After exercise, there was a statistically significant decrease in the initial values of TP in both groups, aligning with the average level of neurohumoral regulation.

CONCLUSION: The results obtained in track and field athletes with a predominant anaerobic training load and skiers with a predominant aerobic load suggest that the training load of a predominantly aerobic nature may lead to less pronounced stress on the regulatory systems. This hypothesis was further supported by the results of the changes in blood pressure.