Power-based training removes guesswork by measuring exactly how hard you are working. Unlike heart rate, power responds instantly to effort changes and is not affected by fatigue, heat, or caffeine.
Understanding FTP
Functional Threshold Power (FTP) is the maximum power you can sustain for approximately one hour. All training zones are calculated as percentages of FTP. Test your FTP every 6 to 8 weeks to track progress and update zones.
The seven zones
- Zone 1 (Active Recovery): below 55% FTP. Very easy spinning.
- Zone 2 (Endurance): 56 to 75% FTP. All-day pace, conversational.
- Zone 3 (Tempo): 76 to 90% FTP. Comfortably hard, can speak in short sentences.
- Zone 4 (Threshold): 91 to 105% FTP. Sustainable for 20 to 60 minutes with focus.
- Zone 5 (VO2max): 106 to 120% FTP. Hard efforts of 3 to 8 minutes.
- Zone 6 (Anaerobic): 121 to 150% FTP. Very hard, 30 seconds to 3 minutes.
- Zone 7 (Neuromuscular): maximum effort, under 30 seconds.
Applying zones to workouts
Each zone targets different physiological adaptations. A well-designed training plan spends most time in zones 1 and 2 (building base), with targeted sessions in zones 4 and 5 (building threshold and VO2max). Zones 6 and 7 are used sparingly for specific race preparation.