Kris Stallenberg 120-min Z2 (Endurance) Medium #05 This session uses descending interval lengths to build mental toughness alongside physical endurance. You'll spend significant time in Zone 2, the cornerstone of aerobic fitness in the Coggan Power Zones model. The longest effort comes first while you are fresh, with subsequent blocks becoming progressively shorter. This structure helps you stay engaged and focused as you accumulate valuable time in the target zone. bike