(1) Background: The performance of physical activity at a sufficient volume can result in improvements in fitness. Aerobic fitness is a particular aspect of fitness that has consistently been shown to be related to both cognitive performance and academic achievement. Cognitive performance, particularly executive function, is itself predictive of academic achievement. It has been hypothesized that the benefits of aerobic fitness for academic achievement are due to improvements in executive function. This study explores the mediating role of cognitive performance on the relationship between physical fitness and academic achievement in high-school-aged adolescents. (2) Methods: High school students (N = 283, 127 male, 156 females, mean age = 16.05 years, SD = 0.41) performed a shuttle run test to assess aerobic fitness and completed the Stroop Color, Stroop Word, and Stroop Color–Word tests to measure information processing and inhibition. They also completed the National Union Academic Achievement Assessment (NUAAA) as part of their high school requirements. (3) Results: Mediation analyses showed that inhibition (performance in the Stroop Color–Word test) fully mediated the relationship between aerobic fitness and both mathematics and Korean performance. (4) Conclusions: This cross-sectional investigation suggests an important mediating role of cognitive performance related to executive function in understanding the relationship between aerobic fitness and the academic achievement of high-school-aged adolescents. This suggests that enhancements in performance related to executive function, which are attributed to increases in aerobic fitness, could explain the observed benefits for academic attainment.

This study aimed to investigate the causes of anger experienced by coaches and to examine the relationships between these causes and different forms of anger expression. A mixed-methods design was employed. First, in-depth interviews were conducted with 10 sports coaches to identify the antecedents of coaches’ anger. Based on these findings, a pilot study involving 44 sports coaches was conducted to develop a questionnaire assessing the causes of coaches’ anger. Subsequently, a quantitative survey was administered to 267 coaches to examine the associations between the causes of anger and anger expression. The results indicated that the primary causes of coaches’ anger were Athletes’ Attitudes, External Circumstances, and Competition Situations. Compared with individual-sport coaches, team-sport coaches were more likely to perceive Athletes’ Attitudes and Competition Situations as major causes of anger. The results of the exploratory structural equation modeling (ESEM) structural model indicated that Competition Situations was negatively associated with outward expression of anger (Anger-Out) but positively associated with active self-regulation (Anger-Control) and internal suppression of anger (Anger-In). External Circumstances was positively associated with Anger-Control, whereas Athletes’ Attitudes was primarily associated with Anger-In. These findings suggest that the relationships among Anger-Out, Anger-In, and Anger-Control vary depending on the underlying causes of anger. Overall, the findings indicate that coaches’ anger is not merely a matter of individual disposition but an emotional response shaped by the complex interplay among coach–athlete relationships, competitive situations, and external factors within the sport environment.