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Background: Observational learning is an effective pedagogical approach that can be used as a method to improve motor skill acquisition and also a useful instrument to promote psychological variables such as self-efficacy by emphasizing the motivational aspect. Although, little research is known about the model type and the observation conditions which will optimize learning. Aim: This study aimed to clarify the effect of using a combination of ideal model-observation and self-observation on self-efficacy and learning the forehand service of table tennis. Materials and Methods: Forty females were assigned to one of four experimental groups. All groups received the same instructions concerning how to perform the task, filled out a self-efficacy questionnaire, and then performed 10 pre-test trials. The acquisition phase included six sessions. The retention test was done 72 hours after the last acquisition session. Mixed ANOVA with repeated measures and Bonferroni post hoc tests were conducted, and one-way ANOVA was used to determine group significant differences. Results: The results indicated that observing the combination of skilled and learning models led to the highest self-efficacy for learning, compare with other experimental models. Also, significant learning of the task was shown in the acquisition phase in which the performance of all three experimental groups was clearly superior to the control group. Although in this phase there was no significant difference between the performances of two groups of combined skilled-learning and skilled. The results of the delayed retention test indicated that the performance scores of the combined skilled-learning group were significantly higher than the other three groups. Also, in this phase, the difference between the combined skilled self-observation and control or skilled groups was not significant. Conclusion: Demonstrating a skilled model is the most popular type of observational learning among the instructors and physical education teachers, it is suggested that adding a learning model to that leads to better performance and enhancing the self-efficacy.

Background : There are conflicting findings regarding the effect of various training modalities on the cardiovascular disease mechanisms induced by undesirable modifications in extracellular matrix (ECM) factors such as MMP-9 and TIMP-1. Aim: This study was conducted to investigate the effect of different training protocols on the MMP-9 and TIMP-1 gene expression in the myocardium of Wistar male rats. Materials and Methods: Forty-eight adult Wistar male rats (aged: 8 weeks) were randomly allocated into two control (Con8w/base, n=8; and Con16w/end control, n=8) and four training groups (MICT, n=8; PICT, n=8; HIIT, n=8; and MIST, n=8). The training protocols consisted of 8 weeks (5 days/week) of Moderate-Intensity, Continuous Training (MICT: 37 min running with 65% vVO 2 max), Moderate-Intensity, Swimming Training (MIST: 30 min free-swimming), Progressive-Intensity, Continuous Training (PICT: 28 min running with a progressive increase in the incline of the treadmill by 2% per week), and High-Intensity Interval Training (HIIT: four running bouts 4 min with 90 to 100% vVO 2 max + 3 min with 50-65% vVO 2 max). Myocardial samples were isolated 24 hours after the last training session. Gene expression was determined using the real-time PCR method. All data (M±SD) were analyzed by one-way ANOVA and Tukey's post-hoc tests at α ≤0.05. Results : There were significant differences between MMP-9 and TIMP-1 expression in the animals myocardium after different exercise training protocols ( P <0.01). The lowest and highest MMP-9/TIMP-1 ratios were in the HIIT and MICT protocols, respectively. Conclusion: According to our findings, the HIIT protocol may play a more influential role in enhancing myocardial ECM-remodeling and fibrosis indicators during lifespan than the other exercise protocols.

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.

The current study aims to explain a communication model for quantum leadership, productivity and empowerment of personnel in the Ministry of Sport and Youth using Interpretive-Structural Modeling approach. The research population included all of the personnel in the Ministry of Sport and Youth, and 269 persons were selected randomly as the research sample. The research tool was questionnaires adopted from the literature for collecting the research data. Twelve sport management experts and Cronbach’s alpha method, respectively confirmed the validity and reliability of the questionnaires. SPSS software and interpretive-structural modeling (ISM) approach were applied to analyze the research data. The results indicated the optimal level in the quantum leadership, as well as personnel productivity, and empowerment. Based on the results, an increase in the level of quantum leadership in the Ministry of Sport and Youth raises the level of personnel productivity, and empowerment. In addition, an increase in the personnel empowerment level in the Ministry of Sport and Youth increases the level of personnel productivity.