Although functional asymmetry is very common and normal in professional athletes, the better interlimb symmetry between dominant and nondominant sides (bilateral symmetry) could contribute to successful performance in basketball. The aim of this study was to evaluate the importance of bilateral symmetry of the one-leg jumping and agility performances in differentiating basketball players according to their (i) playing position (guards, forwards, and centers) and (ii) performance levels (first division vs. second division). The participants were 102 professional male basketball players, with all members of the teams competing in the two highest national divisions at the moment of testing (height: 194.92 ± 8.09 cm; body mass: 89.33 ± 10.91 kg; 21.58 ± 3.92 years of age). Performance levels (first division, N = 58 vs. second division, N = 44) and playing positions (guards, N = 48; forwards, N = 22; centers, N = 32) were observed as dependent variables. We measured one-leg jumping capacities (running vertical jump and lay-up vertical jump), basketball-specific preplanned agility (CODS), and basketball-specific reactive agility (RAG), all executed on dominant and nondominant sides. Accordingly, the bilateral symmetry of jumping and agility was calculated by calculating the ratio of the corresponding performances on the dominant and nondominant sides. Factorial analysis of variance (performance levels × positions) indicated that the bilateral symmetry of one-leg jumping differentiated players according to their playing position, with better bilateral symmetry among guards (F-test = 6.11 (medium effect size) and 5.81 (small effect size), p < 0.05 for lay-up and running-jump symmetry, respectively). Performance levels significantly differed in the bilateral symmetry of lay-up jump, with better symmetry for first-division players (F-test = 10.11 (medium effect size), p < 0.001), which was mostly influenced by significant differences among guards. Playing positions and performance levels did not differ in bilateral symmetry of the CODS and RAG. The study reveals the importance of bilateral symmetry of the sport-specific performance in differentiating playing positions and performance levels in basketball. Further studies in other multidirectional sports and other sport-specific performances are warranted.

Physical literacy (PL) is theorized to be an important determinant of physical fitness (PF) and physical activity levels (PALs), but studies have rarely examined possible correlations between PL, PF, and PAL in preadolescent children. This study aimed to evaluate age-specific and gender-specific correlations between the affective and cognitive domains of PL (PL_AC), PF, and PAL in preadolescents. Additionally, the test–retest reliability of the applied PF tests was examined. The participants were 107 children (9 to 11 years of age; 53 girls). Apart from gender and school age (third graders, fourth graders), the variables included PL_AC, PAL, and PF. PF was evaluated by anthropometrics and body composition indices, sit-ups, push-ups, PACER tests, torso lifts, and broad jump. PL_AC was evaluated using the PLAYself questionnaire, and the PAQ-C was used to evaluate PAL. The test–retest reliability of the PF tests was appropriate to high (ICC: 0.65–0.91). Analyses showed nonsignificant associations between PL_AC and PAL in both genders and age groups. PAL was significantly correlated with PL in girls (low correlation) and fourth graders (moderate correlation). The nonsignificant associations between PL_AC and PF could be a consequence of the influence of biological maturity on PF in this age group. The correlation between PAL and PL_AC can be explained by the differences in physical activity habits between genders and age groups, with participation in structured physical activities (organized sports and physical education) being the most important source of PAL in girls and older children.

Volleyball referees, as athletes and staff members, are exposed to different stress levels which can be determined by measuring pre- and post-match levels of salivary cortisol (C) and alpha-amylase (AA). This study aimed to determine the dynamics of stress biomarkers in referees during official volleyball matches and the connection to the roles or level of competition. The participants in this study were nine international volleyball referees (three females and six males) with a mean chronological age of 48.23 ± 2.31 years. In this study, saliva samples were collected during 24 official matches during the European championship for senior women’s teams (Eurovolley 2021). The AA activity and C concentrations were determined from saliva samples. When the referees’ roles were assessed in line with their duties, the first referees’ salivary C levels showed a significant increase between the pre- and post-match measurements (p = 0.01), while in the second referees remained low. The reserve and challenge referees demonstrated a significant drop in their C concentrations (p = 0.00 and p = 0.02, respectively). Additionally, when assessing AA which accounts for the responsibilities of referees and the intensity of competition, the first (p = 0.06 and p = 0.07) and second referees (p = 0.01 and p = 0.00) showed an increase between the pre- and post-match measurements, respectively. At the same time, the AA activity did not show any significant change concerning the reserve and challenge referees. Our results indicate that referees’ roles and the level of competition may cause higher responses in “active referee roles”—mainly the first and second referees—while reserve and challenge referees showed no increase or even a decrease in the measured biomarkers. The observed changes in the stress markers can be explained by psychological or emotional effects and are dependent on the level of competition and the role referees are fulfilling.

Reactive agility (RAG) is a crucial factor of success in sports, but there are practically no studies dealing with RAG among children. The main aim of this study was to identify predictors of RAG among early pubescent boys and girls. The participants were primary school boys (n = 73) and girls (n = 59) aged 11–12. The criterion variable was the originally developed “Triangle” test of reactive agility (Triangle-RAG). Predictors included anthropometric/body composition indices (body height, seated height, body mass, and body fat percentage) and motor abilities (10 and 20 m sprint, broad jump, squat jump, countermovement jump, drop jump, and two tests of change of direction speed—CODS (Triangle-CODS, and 20 yards)). The results of the univariate analysis showed that anthropometric/body composition indices were not significantly correlated to TRAG (0–4% of the common variance), while all motor abilities were significantly associated with TRAG (7–43% of the common variance) in both genders. Among boys, 64% of the TRAG variance was explained by multiple regression, with TCODS as the only significant predictor. Among girls, multiple regression explained 59% of the TRAG-variance with TCODS, countermovement jump, and drop jump as significant predictors. Differences in multivariate results between genders can be explained by (i) greater involvement in agility-saturated sports (i.e., basketball, tennis, soccer) in boys, and (ii) advanced maturity status in girls. The lack of association between anthropometric/body built and TRAG was influenced by the short duration of the TRAG (3.54 ± 0.4 s). Our findings suggest that pre-pubescent and early pubescent children should be systematically trained on basic motor abilities to achieve fundamentals for further developing RAG. Since in this study we observed predictors including only athletic abilities and anthropometric/body composition, in future studies, other motor abilities, as well as cognitive, perceptual, and decision-making parameters as potential predictors of RAG in children should be investigated.

The aim of this study was to examine the differences in match running performance (MRP) according to the ambient temperature during UEFA Champions League (UCL) matches. Data were collected using an optical tracking system from all teams (n = 32) in all UCL matches (n = 125) during the 2022/23 season, and classified according to the ambient temperature at which matches were played: 21 °C. The results revealed the following: (i) less total distance was covered in matches played at ≥21 °C compared to the matches played at 6–10 °C (d = 0.58), (ii) less high-speed running and high-intensity running were covered in matches played at ≥21 °C compared to the matches played at 11–20 °C (d = 0.54 and 0.43, respectively), 6–10 °C (d = 0.89 and 0.8, respectively), and ≤5 °C (d = 0.62 and 0.57, respectively), and (iii) less sprinting was covered in matches played at ≥21 °C compared to the matches played at 6–10 °C (d = 0.22). These findings indicated the significant differences in MRP when UCL matches were played at different ambient temperatures, with notable reductions in overall and high-intensity efforts in warmer conditions.

Improving physical literacy (PL) is recognized as a potentially effective approach for enhancing overall physical activity (PA) and fitness status, including body composition, but few studies have examined the impact of PL-oriented education on directly measured PA and body composition in children. The aim of this study was to evaluate the effects of a three-month quasi-experimental PL-based educational intervention, delivered as part of the regular physical education (PE) curriculum, in preadolescent children. A total of 119 children aged 9–11 years (51 girls) from southern Croatia participated in the study and were assigned to either a control group (n = 68) or an intervention group (n = 51). The intervention group received a PL-focused educational program integrated into regular PE classes, whereas the control group followed the standard PE curriculum. PA was assessed using accelerometers, and body composition was measured using bioimpedance analysis. A pre–post–retention design was applied (baseline at the start of the school year, post-intervention in December, and retention testing at the end of the school year), and a three-way repeated-measures ANOVA (group × gender × time) was conducted. The intervention prevented declines in vigorous physical activity (VPA) and step count (STEPS) and maintained overall sedentary time (ST) in the experimental group throughout the school year. Significant group × time interaction effects were detected for VPA, STEPS, and ST (F = 4.01, 4.09, and 5.34, respectively; all p < 0.05). No significant effects were found for body composition. In conclusion, the PL-based intervention allowed effective mitigation of the typical seasonal decline in activity levels observed during the school year. Further studies evaluating the effects of similar interventions on other indices of fitness status are warranted.