Kris Stallenberg 45-min Z2 (Endurance) Easy #07 This session is a 'Reverse Endurance Pyramid.' You'll start at the top of your Z2 and gradually step down to the lower end. This front-loads the effort, challenging your aerobic system early in the main set. It's a great way to practice holding a strong pace when fresh and then settling in for the duration, all within the endurance-building Coggan Power Zones. bike