Variability Index

Variability Index measures how smooth (evenly paced) or variable (with frequent changes) your power output was during a ride. It is calculated by dividing Normalized Power by Average Power.

A VI of 1.0 means perfectly even power. Typical values for a steady endurance ride are 1.02–1.06. Interval sessions and races usually produce higher values (1.1–1.3+). Lower VI on similar rides over time suggests better pacing discipline.