4x8 Threshold
75 min · 66-81 TSS · IF 0.77 · 88-95% FTP · Zone 4 (Sweet Spot)
What this workout does
Four solid efforts at threshold. The shorter duration lets you hit the power target precisely - quality over quantity.
Eight-minute reps let you sit right at 95-100% FTP with precision, stacking over half an hour of true threshold time. That raises the effort you can sustain at your lactate turn-point and builds the ability to repeat hard steady efforts. Suits mid-week quality days in a build block.
How to ride it
Indoor / trainer
Warm up 15min. 4x8min at 95-100% FTP with 4min easy between. Cool down 10min.
Outside
Pick any stretch you can ride 8 minutes uninterrupted. Hit 95-100% FTP on each rep - firm but repeatable - and use the 4-minute recoveries to spin completely easy.
Workout structure (75 min)
- Warm-up 15m 55% 4x - Effort 8m 98% - 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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