A plain explanation of the anchor selection rule, what differs between the two, and how the coach overrides it.
The Hub anchors your bike zones to one number: your bike power anchor. That number is Critical Power (CP) when you have a CP test logged, and falls back to FTP when you do not. Same band structure either way; same dashboard layout either way.
This article explains why, what each anchor is, and how the coach controls which one is used.
The Hub used to render two different bike zone schemes:
That meant the "Zone 3" your dashboard described and the "Zone 3a" your activity bar reported were anchored to different numbers and labelled differently. Coaches and athletes had to mentally translate between two systems for the same athlete. Confusing.
The unification replaces both with a single 8-band Yousuli model anchored to the unified bike anchor. The dashboard zone table and the per-activity time-in-zone bars now use the same bands with the same names.
if athlete has Critical Power (CP) logged:
anchor = CP
label = "Critical Power"
else if athlete has FTP logged:
anchor = FTP
label = "FTP"
else:
no bike zones rendered (no anchor available)
The dashboard shows which anchor was picked, the value, and the date it was logged.
Critical Power (CP) is the asymptote of your power-duration curve. Roughly: the highest power you could sustain indefinitely if biological reality let you. It is measured by a CP test that pairs a 3-minute and a 12-minute all-out effort. See CP Test assessment.
The CP test produces two outputs:
FTP (Functional Threshold Power) is your sustainable hour power. It is typically measured with a 20-minute all-out test (and FTP equals 95 percent of the average power from the 20 minutes), or from any clean 1-hour ride.
FTP is older and more universal. Most athletes have it; fewer have CP and W'.
| Aspect | CP | FTP |
|---|---|---|
| Test format | 3-min + 12-min | 20-min |
| Produces W' | Yes | No |
| Test recovery cost | Higher (two efforts) | Moderate |
| Numeric value | Usually 1-3% above FTP | Reference |
| Best for | Modelling time above threshold | Sustained pacing |
For most athletes the two numbers are within 5 watts of each other.
When you have CP:
When you have FTP only:
The coach controls the anchor by deciding which threshold to maintain on the athlete profile:
MetricHistory.MetricHistory entry. The
dashboard updates on next page load.Coaches can also override the anchor for any athlete on their roster regardless of athlete tier (free or premium). Premium athletes have additional self-customization paths that are on the Phase B roadmap.
The upper bands describe efforts above threshold:
Where each band starts and ends depends on W', which quantifies the energy available above CP. Without W', those band edges are guesses. The Hub does not guess: it shows "Need W' data" until a CP test is logged.
See also: Yousuli zones explained, Critical Power Test, Glossary: lactate threshold vs FTP.
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