If pro riders spend the majority of their training time in Zone 2, how much of their lactate threshold improvement is actually attributed to this type of training versus other factors such as specific high-intensity interval workouts and weight training? And given that the average cyclist cant replicate a pros training schedule, whats the point of zone 2 training for us mere mortals if its not the primary driver of lactate threshold improvement? Are we just spinning our wheels (pun intended) by doing hours of zone 2 rides if the real benefits come from more intense, specific workouts?