What influences skill-related fitness and cannot be applied or changed to improve fitness levels?

Skill-related fitness is influenced primarily by genetic factors, such as innate talent and physical attributes like agility, speed, and coordination. Unlike health-related fitness, which can be enhanced through training and lifestyle changes, these inherent traits are largely unchangeable. Additionally, factors like age and specific sports experience also play a role, but they cannot be altered to improve one's skill-related fitness level. Ultimately, while training can enhance performance, the foundational aspects of skill-related fitness are largely predetermined.