W'bal (W' balance) shows how much of your anaerobic reserve remains at any moment during a ride.
Think of it as a fuel gauge for hard efforts:
- 100% = Full tank, ready for hard efforts
- 50% = Half depleted, be cautious
- 25% = Low, hard efforts limited
- <10% = Near empty, exhaustion imminent
How It Works
When You Ride Above Threshold (CP)
Your W'bal drains. The harder you go above threshold, the faster it drains.
When You Ride Below Threshold (CP)
Your W'bal recovers. The easier you go, the faster it refills—but recovery is slower than depletion.
Reading the W'bal Gauge
In the workout player:
W'bal: ████████░░ 78%
TTE: 2:34- Percentage = How much reserve remains
- TTE = Time to exhaustion at your current power (when above threshold)
- ↑80% = Time to recover to 80% at current power (when below threshold)
Color Coding
- Green (>50%) = Plenty of reserve
- Yellow (25-50%) = Getting low
- Red (<25%) = Danger zone
Ghost Arc (2-Minute Projection)
A semi-transparent arc shows where your W'bal will be in 2 minutes if you maintain current power:
- Green ghost = W'bal will be higher (recovering)
- Red ghost = W'bal will be lower (depleting)
This helps you visualize your trajectory and make pacing decisions.
Why It Matters
Without W'bal, you're guessing how long you can sustain a hard effort.
With W'bal, you can:
- Pace climbs without blowing up
- Time attacks knowing exactly how long you can hold the power
- Recover smartly between intervals
- Avoid cracking by watching your reserves
Recovery Rate
W' doesn't refill instantly. Recovery depends on:
- How far below threshold you drop - Lower = faster recovery
- Your individual physiology - Some people recover faster
- Your fatigue level - Tired = slower recovery
The model estimates recovery, but it can vary ±20% between individuals.