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Background: Caffeine is widely recognized as a potent ergogenic aid commonly used to enhance exercise performance and recovery. However, individual responses to caffeine can vary significantly, a variability that might be explained by genetic differences.Aim: This study aimed to investigate the influence of the CYP1A2 rs762551 SNP on the effects of caffeine (CAF) consumption on growth hormone (GH) and testosterone (TS) levels response to resistance exercise (RE) in male athletes.Materials and Methods: Thirty resistance-trained men (mean age 21.72±4.06 years, weight 77.31±14.07 kg, height 179.31±5.08 cm) participated in a randomized, double-blind, placebo-controlled, crossover study. They consumed either CAF (6 mg/kg) or placebo (PL; 6 mg/kg maltodextrin) one hour before performing a RE protocol including three sets with 85% of 1RM and two-minute rest. CYP1A2 genotyping categorized participants as AA homozygous ("fast" metabolizers) or AC heterozygous ("slow" metabolizers). GH and TS levels were measured by ELISA methods.Results: Repeated measures ANOVA showed significant differences in GH levels across time (F=10.94, P=0.000), with significant time-group (F=4.3, P=0.019) and time-genotype-group interactions (F=3.83, P=0.024). One-way ANOVA indicated significant differences in GH levels between CAF and PL conditions in AA individuals, but not in AC/CC genotypes. For testosterone, significant effects of time (F=14.88, P=0.000) and time-group interaction (F=3.197, P=0.045) were observed. Post-RE CAF supplementation significantly increased serum GH and TS levels in AA individuals compared to PL. Both CAF and PL groups showed increased serum hormone concentrations post-exercise.Conclusion: In conclusion, the study demonstrated that caffeine consumption significantly increased serum levels of growth hormone and testosterone in individuals with the AA genotype of the CYP1A2 rs762551 SNP. These findings suggest that genetic variations play a role in the hormonal response to caffeine, which may have implications for exercise performance and recovery strategies.

Several metabolic changes caused by regular exercise, can lead to adaptive mechanisms in athletes. These changes create a new dynamic balance that ensures better performance. On the other hand, because most studies on changes in the metabolic profile of the blood have been conducted in male athletes, this study investigated the effects of different exercise conditions on reactive oxygen species (ROS), adiponectin, and subjective mood in female athletes. A cohort of 30 females, 20 professional players (10 target shooters and 10 basketball players), and 10 sedentary females as control group were enrolled in the study. Capillary blood samples and the Brunel Mood Scale questionnaire (BRUMS) were collected at noon before the training session. ROS and adiponectin were determined by the ELISA method. To compare among groups, one-way analysis of variance and Tukey's post hoc test were used at the significance level of P<0.05. Physiological evaluations showed a significant high level of adiponectin in basketball players (p=0.005). The anger subscale in the basketball group had a significant increase compared to other groups (p=0.04). The tension subscale exhibited a higher level in the shooting group than in the control group. (p=0.017). Regarding the vigor subscale, there was no significant difference in experimental groups, and there was a significant difference in the non-athlete group (control) (p=0.001). Basketball, being a team sport, exhibits a greater degree of aggression in contrast to shooting, which is classified as an individual sport. More focus of coaches on adjusting in another sport with non-competitive and non-confrontational features to reduce anger is suggested.

Isomorphism is the process by which organizations become more similar to each other over time. The purpose of this study was to explore how previous research has examined this phenomenon in sports organizations. We used a semi-systematic approach to conduct the research. In conducting and reporting the review we followed the four stages that are outlined by Snyder (2019). A total of 126 articles underwent an abstract review process, from which 26 articles were extracted. Finally, 13 qualitative articles that related to the research objectives were reviewed. We conducted a content analysis of 13 articles on isomorphism in sport. The articles were published in a variety of academic journals between 1990 and 2023. 8 main themes are presented: Type of isomorphism, Mechanism of isomorphism, Consequences of Isomorphism in Sport Organizations, Function of Isomorphism, Strategies for response to pressure, institutional logics, Application of Isomorphism in Sports Organizations, Managing Isomorphism in Sport Organizations. Results showed isomorphism in sport organizations is driven by three primary mechanisms: coercive isomorphism, mimetic isomorphism, and normative isomorphism. In conclusion, isomorphism is a complex phenomenon that can have both positive and negative consequences for sport organizations. By understanding the mechanisms of isomorphism and carefully managing its effects, sport organizations can leverage its benefits while maintaining their strategic autonomy and fostering a culture of innovation and adaptation.

This research paper presented a comprehensive analysis of the literature on winter sports tourism, tracing its development over a span of 56 years. It was reviewed with bibliometric techniques with VOSviewer software. The extensive bibliometric analysis revealed emerging trends, notable research contributions, and key participants in the field. Prominent countries in this niche are Australia and Canada, while the Universities of Innsbruck and Waterloo, journals such as Sustainability Journal (Switzerland), and authors such as Falk and Muller, Peters, Scottwere have shown significant focus in this area. Therefore, the study highlights the increasing importance of this niche tourism sector, reflecting a surge of interest in recent years as indicated by the rising number of relevant research papers. The review also underscored how vital bibliographic studies are to comprehending the landscape of winter sports tourism. The findings provided trends, patterns, and a roadmap for prospective researchers, flagging the necessity of keeping pace with the evolving realities of winter sports tourism and establishing a valuable foundation for understanding and examining current trends and future developments in winter sports tourism. That will undoubtedly prove useful for both researchers and decision-makers in the field of winter sports tourism.