These four appear in your activity stats (day view → power section). All are calculated by Intervals.icu from your ride data; LeCoach displays them and coaches on them.
Normalized Power (NP)
Average power adjusted for how variable the ride was — surges cost more than steady riding, and NP accounts for that. A stop-start ride with 180w average might carry an NP of 210w; NP reflects the ride's true physiological cost better than plain average.
Intensity Factor (IF)
NP divided by your FTP. An IF of 0.85 means the ride's normalized intensity was 85% of threshold. Rough guide: recovery rides land near 0.5–0.6, endurance 0.6–0.75, tempo/sweet spot 0.75–0.9, threshold work and short races above that.
Efficiency Factor (EF)
NP divided by average heart rate — output per heartbeat. Compared across similar steady rides, a rising EF is aerobic fitness improving. It has its own trend chart in Analytics and pairs naturally with decoupling.
Variability Index (VI)
NP divided by average power — how spiky the ride was. 1.00–1.05 is metronome-steady (well-executed intervals, TTs); above ~1.15 means lots of surging (group rides, crits, punchy terrain). For steady workouts, a high VI is an execution flag — your zone score will usually say the same.