If you train with a power meter, you need to know your zones. Not the three-zone model (easy / moderate / hard) - the seven-zone Coggan system that every cyclist from Cat 5 to WorldTour uses. Here's exactly what each zone is for, how it feels, and how much time you should spend there.
The 7 zones at a glance
| Zone | Name | % FTP | Feels like | Use for | |---|---|---|---|---| | Z1 | Active Recovery | <55% | Barely pedalling | Recovery rides, warm-up, cool-down | | Z2 | Endurance | 56–75% | Conversational | Base miles, fat adaptation, volume | | Z3 | Tempo | 76–90% | "Comfortably hard" | Sweet-spot, long intervals, group rides | | Z4 | Threshold | 91–105% | "I can hold this for an hour" | FTP intervals (2×20min), race pace | | Z5 | VO₂max | 106–120% | "This hurts but I can finish" | 3–8 minute intervals | | Z6 | Anaerobic | 121–150% | "Everything burns" | 30s–3min intervals, attacks | | Z7 | Neuromuscular | >150% | Sprinting | 5–30s sprints, starts, kicks |
How to find your FTP
Before zones mean anything, you need your FTP. Here are three ways:
- 20-minute test: warm up thoroughly, go as hard as you can for 20 minutes, multiply average power by 0.95. This is the gold standard.
- Ramp test: increase power in steps until failure, multiply peak power by 0.75. Easier to execute but slightly less accurate.
- Critical power model: your best 3-minute and 12-minute power from recent rides. CP12min ≈ FTP.
Use the Baseline FTP calculator for quick estimation.
What the research says about distribution
The single most replicated finding in endurance training science: polarised training works.
About 80% of your training time should be in Z1–Z2 (easy). About 20% should be in Z4+, with very little in Z3 - the "grey zone" that's too hard to be recovery and too easy to be a stimulus.
Baseline tracks your actual time in each zone automatically and shows you over weeks and months whether your distribution is effective. Most amateur cyclists spend 40–50% in Z3 without realising it. The fix is simple: ride easier on easy days, ride harder on hard days.
The sweet-spot debate
Sweet-spot training (88–94% FTP, roughly high Z3/low Z4) has become popular because it feels productive - hard but not brutal. You can do 2–3 sweet-spot sessions per week and accumulate a lot of time at a meaningful intensity.
The tradeoff: sweet-spot is fatiguing enough to reduce the quality of your truly hard sessions (Z5+) but not hard enough to be maximally effective on its own. For time-crunched cyclists (4–6 hours/week), sweet-spot is a reasonable compromise. For cyclists training 10+ hours/week, true polarised distribution (80% easy, 20% hard) produces better results.
Zone drift during long events: why your zones change mid-ride
A power zone is a fixed wattage range based on your FTP - 200 watts is 200 watts whether you are at minute 5 or hour 5 of a ride. But the physiological cost of holding 200 watts changes dramatically over a long event due to cardiac drift. As you dehydrate, your plasma volume drops, which reduces stroke volume. To maintain cardiac output at the same power, your heart rate rises. A Z2 power effort at minute 30 can feel like Z3 by hour 4 even though the power output has not changed.
This is why experienced endurance riders and racers use power as their primary target for the first half of a long event and switch to heart rate or RPE in the second half. You do not change your target zones - you change your reference. For a 5-hour ride: ride at 70% of FTP for the first 3 hours (power-guided Z2), then ride at the heart rate that normally maps to 70% of FTP for the final 2 hours even if that means power drops 10-15 watts. Your muscular endurance is the limit, not your cardiovascular system, and respecting cardiac drift prevents the late-race implosion.
The same principle applies to multi-day stage races and training blocks. Your FTP - and therefore every zone - can drop 3-8% by day 3 of a stage race due to accumulated fatigue and glycogen depletion. Ignoring this and trying to hit day-1 power targets on day 3 produces catastrophic failures. Pros adjust their power targets daily based on morning HRV and subjective feel. Amateurs tend to stubbornly stick to the same power file every day and wonder why they crack.
Baseline tracks not just your zones but your actual power-zone compliance: whether you hit your prescribed zone targets in a session and how your zone adherence drifts across successive days. A session that looks "completed" on paper might have been performed at a 5-watt deficit across every interval, which accumulates into meaningful undertraining.
How Baseline helps
Connect your power data through Strava or Garmin. Baseline automatically computes your FTP from best efforts, tracks your zone distribution over time, and shows whether you're training polarised or falling into the grey zone. The AI insights card flags when your distribution drifts - so you can fix it before it becomes a habit.
Common mistakes
1. Living in Zone 3. The most common mistake amateur cyclists make is spending the majority of their training time in Zone 3 - the "grey zone" that is too hard to be recovery and too easy to be a meaningful training stimulus. It feels productive because you are working hard, but it undermines both your easy days (you do not recover enough) and your hard days (you are too fatigued to hit true VO2max or neuromuscular intensity). The fix is simple: ride easier on easy days and ride harder on hard days. If your zone distribution shows more than 10-15% of total time in Z3, you have room to polarise.
2. Using stale FTP to set zones. Your power zones are only as accurate as your FTP. If you set your FTP six months ago and have not retested, every zone is likely wrong. A 20W change in FTP shifts your Z2 ceiling by 15W and your Z4 floor by 10W - enough to make your threshold intervals either trivial or impossible to complete. Set a recurring reminder to retest every 4-6 weeks during build phases and every 8-12 weeks during maintenance.
3. Neglecting Z1 and Z2 volume. Polarised training consistently produces the best results for endurance athletes, which means 80% of your training time should be below Z3. Many cyclists chase the feeling of a hard workout and skip the easy volume that builds the aerobic foundation. Without sufficient Z2 base miles, your high-intensity work lacks the aerobic support it needs to be effective. Your engine needs a big base before you can build a powerful top end.
How Baseline handles this
Baseline automatically computes your power zones from your current FTP and tracks your time-in-zone distribution across every ride. The Training Load screen shows your weekly and monthly zone breakdown, comparing your actual distribution against polarised model targets. When your Z3 proportion creeps above 15%, the AI insights card flags it and suggests adjustments to your weekly structure.