Z1 : Zone 1: active recovery
LoadThe easiest effort, where you could recite a poem without panting.
Z1 sits around 55-75% of FTP on the bike, or < 80% of CSS in the swim. It's used for recovery jogs, cool-downs and easy mobility days. No meaningful aerobic stimulus : just blood flow and movement quality.
In TriPaced:
In TriPaced, Z1 mostly shows up on recovery weeks and after hard sessions. It can feel close to walking pace : that's intentional, the goal is zero added fatigue.