This book provides a multidisciplinary examination of the comprehensive transformation of modern sports within the framework of globalization, digitalization, and international policy. The chapters explore a wide range of topics, from the physiological and psychosocial adaptation processes in athlete migration to the strategic role of elite performance as a "soft power" tool in the international arena. Modern approaches in training science are integrated with biological rhythms and recovery strategies, while contemporary issues such as identity construction in digital sports culture and the emerging risks of digital fatigue among youth are presented through literature-based analyses. Furthermore, the book discusses the mental health dimension of sports, focusing on help-seeking behaviors and the critical social role of sports in preventing violence and peer bullying through theoretical frameworks. This work serves as a holistic guide for researchers, coaches, and practitioners seeking to understand both the performance continuity of professional athletes and the evolving sociological dynamics of sport.