Kris Stallenberg 90-min Z2 (Endurance) Easy #06 This session simulates rolling terrain by alternating between the lower and upper ends of your endurance zone. These subtle shifts in intensity, while staying entirely within Z2 of the Coggan Power Zones, train your body to adapt to changing power demands efficiently. This enhances metabolic flexibility and muscular endurance. Focus on smooth transitions between the power levels, as if cresting a small hill and descending into a dip. bike