Final answer:
The factor that is NOT important for performance in endurance events is c) 'high anaerobic capacity', as endurance events rely on aerobic metabolism rather than short bursts of high intensity that require anaerobic capacity.
Step-by-step explanation:
The correct answer to the question 'Which of the following is NOT an important factor that contributes to performance in endurance events?' is c. high anaerobic capacity. Endurance events typically require a sustained effort over a longer period, which primarily relies on aerobic metabolism.
Superior exercise efficiency/economy relates to how effectively the body uses energy for movement, and a high VO₂ max indicates the maximum volume of oxygen an individual can use during intense exercise, both being crucial for endurance. Conversely, a high lactate threshold allows an individual to maintain a high-intensity exercise longer without fatigue. While anaerobic capacity is essential for short bursts of high-intensity activity, as seen in sprinting, it is not a significant component of long-duration endurance events.