3x12 Threshold
70 min · 69-84 TSS · IF 0.80 · 95-100% FTP · Zone 4 (Sweet Spot)
What this workout does
Three twelve-minute efforts right at threshold. Long enough to drive real adaptation, short enough to hold clean, even pacing from start to finish.
Twelve minutes at 95-100% FTP is long enough to fully load the aerobic system at your lactate turn-point, pulling sustainable effort upward. Three reps stack 36 minutes at threshold - a strong dose that still allows clean, even pacing. Place it early in the week on fresh legs.
How to ride it
Indoor / trainer
Warm up 15min. 3x12min at 95-100% FTP with 5min easy between. Cool down 5min. Settle in by minute two and hold steady.
Outside
Use any road or loop you can ride 12 minutes without interruption. Build into each rep over the first minute, then sit at 95-100% FTP - hard but even, breathing rhythmic - and soft-pedal 5 minutes between.
Workout structure (70 min)
- Warm-up 15m 55% 3x - Effort 12m 98% - 5m 55% - Cool-down 5m 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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