Zone 2 training serves as a foundational element that enables individuals to accumulate the high volume of exercise necessary for long-term physiological adaptation without excessive fatigue.

“I think zone two is the cornerstone that lets you do enough work, enough volume safely and consistently, so that you get the adaptations you need to be an athlete for life.”

While zone two training is an effective strategy, it is not strictly necessary for maximizing VO2 max if an individual is time-pressed.

“For the individual who is time-pressed, I don't think there's a need to do three to four hours of what I understand to be zone two training weekly in order to maximize improvements in VO2max.”