Kris Stallenberg 60-min Z2 (Endurance) Medium #10 This workout focuses on the upper end of Zone 2, often called 'sweet spot minus'. Riding at this intensity (around 74% FTP) provides a strong aerobic stimulus without the lactate accumulation of higher zones. According to Coggan Power Zones, this is a highly effective intensity for improving aerobic fitness. The two long blocks will challenge your ability to maintain focus and consistent power output for extended periods. bike