Cycling · Threshold
SEILER 4 × 16
4 × 16 min at the highest sustainable power, 2–3 min easy
THE STORY
The longest of the three formats Stephen Seiler's group compared (4 × 4, 4 × 8 and 4 × 16 minutes). In that study it gained a little less than 4 × 8 — but it's a superb long-threshold session in its own right.
Sources
- Adaptations to aerobic interval training: interactive effects of exercise intensity and total work duration — Scandinavian Journal of Medicine & Science in Sports (PubMed), 2013
WHAT IT TRAINS
Long threshold work with very short breaks — over an hour of near-threshold riding.
WHO IT'S FOR
Well-trained endurance riders and long-course triathletes.
HOW TO DO IT
- 01Warm up 15 minutes.
- 024 × 16 minutes at the highest power you can hold for all four (around 95% FTP).
- 032–3 minutes easy between.
- 04Cool down 10 minutes.
SCALED VERSION
3 × 12 minutes at 90–95% FTP.
Build the scaled version in Forge →TARGETS THAT FIT YOU
Every target is a percentage of FTP. Your Garmin applies it to the FTP saved on your device or in Garmin Connect, so the same workout fits every rider — keep your FTP up to date.
THE WORKOUT, STEP BY STEP
CYCLING1h 39min
Seiler 4 × 16
4 × 16 min at the highest sustainable power, 2–3 min easy · Inspired by Stephen Seiler. · Fit File Forge Workout Library: www.fitfileforge.com/workouts/library/seiler-4x16
WARMUP15 minTarget: 50-75% FTP
Build from 50% to 75% FTP.
INTERVAL16 minTarget: 93-97% FTP
Highest you can hold for all four.
RECOVERY2m 30sTarget: 48.5-51.5% FTP
Easy.
COOLDOWN10 minTarget: 48.5-51.5% FTP
RELATED WORKOUTS
- CyclingVO2maxDifficulty 4 of 5 — Very hard
Seiler 4 × 8
4 × 8 min at the highest power you can hold for all four, 2 min easy
1 h 10Inspired by Stephen Seiler - CyclingThresholdDifficulty 3 of 5 — Hard
Classic 2 × 20 FTP
2 × 20 min at 95–100% FTP, 5–10 min easy
1 h 15 - CyclingSweet spotDifficulty 3 of 5 — Hard
3 × 20 Sweet Spot
3 × 20 min at 88–94% FTP, 5 min easy
1 h 35
NOT HERE? DESCRIBE IT.
Type any session the way you'd tell a training partner — Forge turns it into a Garmin workout in seconds, and your coach can plan the weeks around it.
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