Anaerobic Capacity Builder
65 min · 53-65 TSS · IF 0.73 · 120-130% FTP · Zone 6 (Anaerobic)
What this workout does
Short, supra-VO2max efforts to develop your anaerobic system. These intervals target the zone between VO2max and sprint power — the range where you attack, surge, and respond to moves in races.
Two minutes at 120-130% FTP overloads the anaerobic system, expanding the energy you can release above threshold and your tolerance for the burn that follows. Each rep also spills into VO2max territory by its end, so the aerobic ceiling gets a secondary stimulus. Best in the later build phase when a solid aerobic base can absorb it.
How to ride it
Indoor / trainer
Warm up 20min. 6x2min at 120-130% FTP with 4min easy between. Cool down 10min. Start conservatively; pace to finish the last rep at target power.
Outside
A quiet road or short climb of about 2min. Ride each rep at 120-130% FTP - a hard, controlled surge, not a sprint - and take the full 4min easy spin so the next rep can match it.
Workout structure (65 min)
- Warm-up 20m 55% 6x - Effort 2m 125% - 4m 55% - Cool-down 10m 55%
Targets are a percentage of FTP. This is the same shorthand the free workout builder understands — paste it there to edit any step, or download the workout for Zwift, Garmin or any smart trainer.
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