The second volume includes the essential sports biology and training science fundamentals that are important for understanding the training of the main motor demands: flexibility, endurance, and coordination skills. The presentation of the cardiovascular and respiratory systems, as well as the nervous system, precedes the sections on endurance and coordination training. Both flexibility and endurance, along with coordination skills, are discussed in terms of their significance for athletic performance and health. A key focus is the description of suitable training methods and content for their development across different age groups. Due to its importance for performance preparation and recovery, warm-up and cool-down routines, along with their performance-optimizing mechanisms, are explored in depth. Other key topics include temperature regulation, the hormonal system, nutrition, and doping issues. The chapter 'Sport and Health' concludes the volume, highlighting its outstanding importance due to the multitude of modern diseases related to physical inactivity and the associated explosion of costs in healthcare.