The aim of this research was to determine the connection between the level of physical activity and body composition among school-age children. The sample of participants included 479 students, 250 boys and 229 girls, school-age children, with an average age of 12,5±1,08. Their level of physical activity was evaluated using the FELS PAQ questionnaire, while their body composition was evaluated using the BIA method. To determine a connection between the group of predictor variables and the criterion variables, a canonical correlation analysis was used. The obtained results indicated that there is a positive correlation between the level of physical activity and the parameters of body composition, both for the sample of school-age boys (p= .002), and the sample of girls (p= .048). It could be concluded that the participants who were physically more active scored lower values for Body Fat and BMI, that is, higher values for Muscle Mass and Lean Body Mass.

The process of aging leads to changes in functional abilities, fitness levels, level of physical activity, and body mass index (BMI), all of which causes changes in the quality of life. The current study aims to determine the association between the level of physical activity (PA) and BMI, and quality of life (QoL) among elderly women. The total sample numbered 156 women, with an average age of 67.7 ± 5.6 years. To determine the level of physical activity, the self-reported International Physical Activity Questionnaire Long Form (IPAQ-LF), was used. To calculate the values of the BMI, the standard procedure recommended by the World Health Organization was used. Quality of life was evaluated using the short form of the WHOQOL-BREF questionnaire designed by the World Health Organization. All the data were processed using the statistical package for data analysis SPSS 20.0. Pearson’s correlation analysis shows statistically significant relations at the level of p < 0.01 between PA and Physical health in Housework = 0.36, Leisure time PA = 0.27, Walking = 0.24, Moderate PA 0.43, Total PA = 0.43, while the correlations between the variables at the significance level of p < 0.05 were determined in PA in transportation = 0.19 and High-intensity PA = 0.16. Multiple linear regression analysis of different levels of PA as independent variables on individual domains of QoL shows that there is an association of PA and Physical health (Sig = 0.000), more precisely, Total PA is statistically the most closely related to Physical health (Sig = 0.000), and then follows PA at work and Social relations (Sig = 0.036). Similar results were obtained when BMI is added to model A. In contrast to model A, model B shows a statistically significant association between PA and BMI with the environmental domain of QoL (Sig = 0.001). The results of the current study indicate that high- and moderate-intensity physical activity both have benefits for physical health, whereas moderate PA showed higher significance levels. Results also show that elderly women with higher BMI values achieve better results in the environmental domain of QoL.

The aim of this study was to establish the role of maturation on the development of physical performance in adolescent athletes and nonathletes. The total studied sample consisted of 231 participants (131 athletes: 72 boys with an average chronological age of 13.53 ± 0.7 and 59 girls with an average chronological age of 11.97 ± 0.8; 100 nonathletes: 47 boys with an average chronological age of 13.73 ± 0.47 and 53 girls with an average chronological age of 11.93 ± 0.33), distributed according to their biological maturity stage (Pre-, Mid-, and Post-Peak Height Velocity [PHV]) and to their gender. The assessment of physical performance was performed using the following tests: Countermovement jump (CMJ), countermovement jump with arm swing (CMJA), squat jump (SJ), five-jump test (5JT), 5 m sprint (5 m), 10 m sprint (10 m), 20 m sprint (20 m), T-test, Zig Zag, and Slalom. The differences in athletes according to biological maturity were identified in all variables except for 5 m (p = 0.33) and Slalom (p = 0.07), while in nonathletes the differences were found in 5JT (p = 0.01), 5 m (p = 0.02), 10 m (p = 0.01), and 20m (p = 0.01) tests. Additionally, a significant interaction of gender and biological maturity was detected for CMJ (p = 0.03), CMJA (p = 0.01), and Zig Zag (p = 0.05) in athletes. The findings of the current study confirm the importance of maturity status in the assessment of physical performance. As a consequence, a more rational selection of talented athletes could be provided, also enabling the timely development of physical performance in nonathletes as a “window of opportunity”.

The aim of this research is to contribute to the understanding of the concept of satisfaction with life by determining the relationship between personality traits and the subjective experience of satisfaction with life in students—recreational athletes. This research is based on the biological theory of personality by Hans Eysenck and it attempts to offer explanations of a possible change in satisfaction with life in the period of great social deprivation caused by the Covid-19 pandemic. The sample of subjects consisted of 120 undergraduate students (N = 120) of all years and both sexes, 55 (45.8%) males and 65 (54.2%) females, at the Faculty of Sport and Physical Education, the University of Nis. The average age of the subjects was 23.63 years (SD = 2.070). Eysenck's personality questionnaire (Eysenck Personality Questionnaire, EPQ: Eysenck et al., 1885, adapted and translated by Šipka, 1985) was used for the operationalization of personality structure. The SWLS scale (Satisfaction With Life Scale, Diener et al., 1985) was used for estimating satisfaction with life. A significant regression model, which explains 11% of variance in the subjective experience of satisfaction with life in recreational athletes, was obtained. In the model, extraversion stands out as a significant predictor from the group of personality traits (β = 0.279). Neuroticism (β = −0.160) and psychoticism (β = −0.122) did not prove to be significant predictors of satisfaction with life in the structural model regardless of there being a significant negative correlation between neuroticism and satisfaction with life. The more extraverted participants had a keener subjective sense of satisfaction with life.

Body mass index (BMI) and body image (BI) are constructs worth examining in the context of physical activity (PA), and they are both related to quality of life (QoL). PA, BMI, and BI should all be considered as associated parameters, and their effect on QoL should be examined and understood. This study aimed to determine the moderating role of PA in the relationship of BMI and BI with QoL. The sample of examinees consisted of 500 respondents (307 women; aged 39 ± 6 years). A physical activity self-evaluation questionnaire (IPAQ-SF) was used to estimate PA; BI was evaluated by using the Body Image Dimensional Assessment (BIDA) questionnaire, while QoL was determined with the WHOQOL-BREF questionnaire. The results showed that vigorous PA moderates the relationship between BMI and social relationships in adults (Sig. = 0.000). Walking and vigorous PA affect the relationship between BMI and environmental health (Sig. = 0.017 and Sig. = 0.049, respectively). Both walking (Sig. = 0.035) and moderate PA (Sig. = 0.032) alternate the relationships between BI and social relationships. Walking (Sig. = 0.000) and vigorous PA (Sig. = 0.016) moderate the relationship between BI and environmental health. The influence of PA on the moderation of the relationship of BMI and BI with physical and psychological health in the working population was not statistically significant.