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This review article elucidates the structure and critiques the effects of social loafing in the team sport of volleyball. Drawing upon existing theories, opinions, and research, this review addresses the conceptual framework and factors influencing individual and group behaviors in sports environments, particularly volleyball. These factors include team cohesion, leadership styles, communication, interdependent tasks, and individual motivation. An examination of the research methodologies and article formulations, as well as meta-analyses in academic databases like PubMed, Google Scholar, and PsycINFO, indicates that the predominant approach in studies on this phenomenon is deductive, with survey strategies employed through observational studies and interviews with players and coaches using questionnaires. The findings of this review, on one hand, present and analyze theories and models explaining social loafing behaviors in sports environments and teams, including the processes and dimensions of the emergence (and growth) of social loafing and its impact on individual aspects and team performance in volleyball. On the other hand, it highlights key points and related solutions for future research directions in volleyball, including strategies and interventions (by coaches and team leadership) aimed at reducing social loafing, enhancing cohesion, and improving group dynamics in volleyball teams, ultimately leading to improved team performance.

Fatigue is a common and debilitating symptom among older adults, significantly impacting their quality of life and functional capacity. The relationship between serotonin and fatigue in aging is complex, involving multiple neurobiological pathways that influence sleep, mood, cognitive function, and energy metabolism. Understanding these mechanisms is crucial for developing effective management strategies. This review aims to elucidate the role of serotonin in the development of fatigue in elderly individuals and evaluate potential therapeutic strategies to mitigate this condition. A comprehensive review of recent literature was conducted, focusing on the neurobiological mechanisms linking serotonin to fatigue, the efficacy of pharmacological and non-pharmacological interventions, and future research directions. Studies were selected based on their relevance to serotonin’s role in aging and fatigue management. Serotonin plays a critical role in regulating various physiological and psychological functions that impact fatigue. Age-related declines in serotonin synthesis, receptor sensitivity, and transporter function contribute to increased fatigue through disrupted sleep, mood disorders, cognitive decline, and altered energy metabolism. Pharmacological treatments, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), have shown efficacy in alleviating fatigue related to depression and chronic pain. Non-pharmacological interventions, such as cognitive behavioral therapy (CBT), exercise, sleep hygiene, and dietary modifications, are also effective in managing fatigue. Combining these approaches may offer the best outcomes for elderly patients. Addressing fatigue in older adults requires a multifaceted approach that integrates both pharmacological and non-pharmacological strategies. Personalized treatment plans considering individual patient profiles and preferences can enhance therapeutic efficacy. Future research should focus on exploring novel therapeutic targets within the serotonergic system, developing personalized medicine approaches, and evaluating the long-term impact of combined therapies.

Background : Cold sprays (CS) are widely used in sport competitions as an effective, simple, and high available treatment. Aim: The aim of present study was to investigate immediate and longtime effects of CS application onto the knee joint anterior-medial area of dominant leg on timing and activation pattern of selected muscles during one-leg landing. Materials and Methods: Thirty (15 control and 15 experimental) able-bodied male participated in this study. Electromyography activity of vastus medialis, rectus femoris, vastus lateralis, biceps femoris, semiendineus and medial gastrocnemius were recorded during one-leg landing tests (with dominant leg) for each of three conditions including before CS application (pre-test), immediately after (post-test 1), and 20 min later (post-test 2). To determine the effect of group and time on each dependent variable, three independent 2×2 multivariate repeated measures analyses of variance were performed (α < 0.05). Results : The results showed following trends rather than significant differences: the muscles in the experimental group had lower activity level and later onset immediately after CS application compared to before application, and they had higher activity level and sooner onset after 20 min from removing CScompared to immediate application. No significant interaction was found for normalized peak activation and time to peak activation ( P > 0.05). However, decrease in skin temperature after cold spray application was observed. Conclusion : These results show short-time cold application, which is so practical after many injuries for returning athletes to sport environment, may not predispose individuals to risk of re-injury or failed landing mechanism.

Purpose: The aim of this study was to investigate the acute effects of HIFT exercise, on creatine kinase (CK) and lactate dehydrogenase (LDH) in blood serum in overweight adult men. Method : Twenty-two untrained non-smoker overweight men (age, 42.9 ± 5.6 years; body mass, 94.2 ± 9.3 kg; body height, 178.9 ± 4.5 cm; and BMI, 29.04 ± 3.3 kg/m2) volunteered to participate in this study and performed a session of HIFT exercise with 80-85% HRmax consisting of three sets of 10 exercises. Blood samples were collected before and immediately after training to measure serum CK and LDH levels. Results: The HIFT protocol significantly increased serum CK (Pre: 114.6 U/L; Post: 124.3U/L; p< 0.05{t=-5.48, p=0.001}); Also, LDH had a significant increase (pre:213.4 U/L, post: 225.4U/L; p<0.05{t=-4.09, p=0.001}). Conclusion: It can be concluded that HIFT with AMRAP (as many repeats as possible) protocol will lead to a significant increase in some indicators of muscle damage such as CK and LDH levels in overweight men. This protocol can lead to muscle damage in overweight men.

The purpose of the current research was to investigate and prioritize the promoting and inhibiting factors in the development of women's professional basketball in Khorasan Razavi, Iran. This is a mixed study conducted with an exploratory-analytical approach. In the qualitative part of the research, the interviewees included sports management professors, prominent basketball pioneers in Khorasan Razavi province, professional female basketball players, as well basketball boards’ managers and representatives. In the quantitative phase, the statistical population included professional female basketball players, coaches, and basketball pioneers in Khorasan Razavi. In general, 8 interviews and 134 questionnaires were collected in the research process. The qualitative data was analyzed through the content analysis method while the quantitative data analysis process was completed by using SPSS software (v. 22) and exploratory factor analysis, as well as Friedman's ranking tests. The findings of the research revealed that out of 48 items obtained as effective factors on the development of women's professional basketball in Khorasan Razavi province, 25 items were considered as promoting factors and 23 items were found as inhibiting factors. Also, based on the results of the exploratory factor analysis test, 6 promoting factors ("socio-cultural factors", "technical level", "basic factors", "expert human resources", "competition and event", and "scientific indicators") and 5 inhibiting factors ("financial issues", "motivational supportive factors", "facilities factor", "club ownership" and "management perspective”) were identified. "