Kris Stallenberg 45-min Z2 (Endurance) Pushing #10 The Disciplinarian workout demands focus. You'll alternate between the very top and the very bottom of the endurance zone with no true rest. This teaches your body to recover while still working, a crucial skill for long events. This strict adherence to the boundaries of Z2, as defined by Coggan Power Zones, builds a highly efficient and resilient aerobic engine. bike