Pedro Morouço ^1* Aleksandra Maria Rogowska ^2,3 Behzad Behzadnia ⁴

• ¹ Polytechnic Institute of Leiria, Leiria, Portugal
• ² Institute of Psychology, University of Opole, Opole, Opole, Poland
• ³ Institute of Psychology, University of Opole, Poland, Opole, Poland
• ⁴ University of Tabriz, Tabriz, East Azerbaijan, Iran

The contributions in this issue span a broad spectrum of research areas, from theoretical explorations of motivational constructs to practical interventions aimed at fostering physical activity. Collectively, they enrich our understanding of how motivational processes operate in diverse settings and populations. The relationship between self-efficacy and motivation is foundational in understanding physical activity behaviors across different stages of life. Yuexian Tao et al. investigate the links between self-efficacy and motivation levels among emerging adults through the lens of self-determination theory. Their findings underscore the importance of fostering intrinsic motivation to enhance physical activity levels in this critical developmental stage. Similarly, Erik Grasaas and Øyvind Sandbakk analyze trends among Norwegian adolescents, revealing positive associations between self-efficacy and adherence to physical activity recommendations. Individual differences in personality and psychological characteristics shape how people engage with physical activity. Weipeng Zhang et al. delve into the dualistic model of passion to examine how self-oriented perfectionism influences exercise participation. This study highlights the nuanced role of personality traits in shaping physical activity behaviors. Complementing this, Yuan Zhang et al. explore procrastination's impact on physical activity among university students, identifying the chain-mediated roles of time management and exercise motivation. The role of the social and physical environment is crucial in shaping early and sustained engagement in physical activity. The family environment emerges as a critical determinant in Ting Huang et al.'s study, which explores associations between family factors and physical activity clustering in preschool children. This emphasis on early life determinants aligns with the national-level analysis by Mingming Guo et al., who examine recreational screen time and its impact on Chinese children and adolescents' activity levels. The insights offered by this special issue place the study of physical activity motivation within a broader context of contemporary behavioral science. They reflect the multidimensionality of motivation, emphasizing that sustaining engagement in physical activity demands an integrative approach-one that accounts for individual, social, and environmental factors.Looking ahead, the field stands poised for significant developments. Emerging technologies, such as AI-driven or web-based personalized interventions, and the growing recognition of cultural and contextual factors, offer promising avenues for further exploration. Additionally, experimental and longitudinal research are crucial to explore the long-term effects of motivational strategies for physical activity adherence. The studies featured in this special issue collectively advance our understanding of the complex dynamics that motivate individuals to engage in physical activity. By addressing diverse populations and using various theoretical frameworks, they provide a robust foundation for future research and practice. It is our hope that these contributions will encourage further innovation and collaboration toward healthier, more active societies.