Final answer:
The statement is false because the ATP-PC system predominates only in very short, intense activities like short sprints, and is exhausted within 8-10 seconds. Longer sprints and middle-distance runs rely more on anaerobic and aerobic systems, respectively.
Step-by-step explanation:
The ATP-PC system is not the predominant system used during longer sprints and middle distance runs; thus, the statement is false. The ATP-PC system, which relies on using creatine phosphate to regenerate ATP, provides energy very quickly but it is exhausted within approximately 8-10 seconds. This makes it ideal for very short, intense activities like heavy weightlifting or short sprints. In longer sprints and middle-distance runs, other energy systems become more important, such as the glycolytic system (anaerobic metabolism) and, over longer distances, the aerobic system.