What Are Power Zones and Why Do They Matter?
Training by feel is fine when you're starting out, but if you want to make structured, measurable progress on the bike, power zones are your most valuable tool. Unlike heart rate, power output is instantaneous — it reflects exactly how hard you're working right now, not how hard you were working 30 seconds ago.
Power zones divide your effort into distinct bands, each targeting different physiological adaptations. Spending the right amount of time in each zone is what separates strategic training from simply putting in kilometres.
How to Find Your Functional Threshold Power (FTP)
All power zones are calculated as a percentage of your Functional Threshold Power (FTP) — the maximum average power you can sustain for approximately one hour. The most common way to test this is the 20-minute FTP test:
- Warm up thoroughly for 15–20 minutes, including a few short hard efforts.
- Ride as hard as you can sustain for exactly 20 minutes on a flat or slightly uphill road.
- Record your average power for those 20 minutes.
- Multiply that number by 0.95 — this is your estimated FTP.
Re-test your FTP every 6–8 weeks to track progress and keep your zones accurate.
The 7 Power Zones Explained
| Zone | Name | % of FTP | Purpose |
|---|---|---|---|
| 1 | Active Recovery | < 55% | Easy spinning, recovery rides |
| 2 | Endurance | 56–75% | Aerobic base building |
| 3 | Tempo | 76–90% | Sustained effort, race simulation |
| 4 | Lactate Threshold | 91–105% | Raising your FTP ceiling |
| 5 | VO2 Max | 106–120% | Maximal aerobic capacity |
| 6 | Anaerobic Capacity | 121–150% | Short, very hard efforts |
| 7 | Neuromuscular Power | > 150% | Sprint power and explosiveness |
How to Structure a Training Week with Zones
A well-rounded training week should not be spent entirely at high intensity. Overtraining is one of the most common mistakes cyclists make. A proven distribution is the 80/20 rule: approximately 80% of your training time in Zones 1–2, and 20% in Zones 3–7.
- Monday: Rest or Zone 1 recovery spin (30–45 min)
- Tuesday: Interval session — Zone 4 or 5 efforts (60–75 min)
- Wednesday: Zone 2 endurance ride (90 min)
- Thursday: Tempo work — sustained Zone 3 (75 min)
- Friday: Rest or light Zone 1
- Saturday: Long Zone 2 ride (2.5–4 hours)
- Sunday: Group ride or race simulation
Getting the Most from Zone 2 Training
Many cyclists underestimate Zone 2. It feels too easy, so they push harder. But consistently riding in Zone 2 builds your aerobic engine — the foundation everything else sits on. You should be able to hold a conversation during Zone 2 riding. If you can't, you're working too hard.
Key Takeaways
Power zones remove the guesswork from training. Test your FTP regularly, follow a structured weekly plan, and resist the urge to go hard every day. Progressive, zone-based training is what delivers consistent performance gains over a full season.