Interesting question! During Zone 2 training, your body undergoes several adaptations. One key change is improved fat oxidation, allowing your body to use fat as a fuel source, sparing glycogen. This could potentially aid recovery by reducing muscle damage caused by high-intensity training.
However, the concurrent reduction in high-intensity training stress might also play a significant role. By reducing the overall training load, your body can dedicate more resources to recovery and adaptation.
So, while Zone 2 training itself can stimulate specific adaptations, the improved recovery might also be a result of the reduced high-intensity training stress. It's a complex interplay, and both factors could be at play.