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Cycling · VO2max

SEILER 4 × 8

4 × 8 min at the highest power you can hold for all four, 2 min easy

Time · 1 h 10Difficulty · Difficulty 4 of 5 — Very hardVery hardInspired by · Stephen Seiler

THE STORY

From research by Stephen Seiler and colleagues: trained cyclists doing 4 × 8-minute intervals twice a week for seven weeks improved more than groups doing 4 × 4 or 4 × 16 minutes. We use 2-minute recoveries.

Sources

  1. 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

A 'maximal sustainable' effort just above threshold — a sweet spot between intensity and total time.

WHO IT'S FOR

Trained cyclists and triathletes. Pace the first rep so the fourth is as strong.

HOW TO DO IT

  1. 01Warm up 15 minutes with a couple of short openers.
  2. 024 × 8 minutes at the highest power you can hold for all four (typically about 105% FTP).
  3. 03Spin easy for 2 minutes between.
  4. 04Cool down 10 minutes.

SCALED VERSION

4 × 6 minutes at 100–105% FTP with 2 minutes easy.

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 05min

Seiler 4 × 8

4 × 8 min at the highest power you can hold for all four, 2 min easy · Inspired by Stephen Seiler. · Fit File Forge Workout Library: www.fitfileforge.com/workouts/library/seiler-4x8

WARMUP15 minTarget: 50-75% FTP

Build from 50% to 75% FTP.

4×Repeat

INTERVAL8 minTarget: 103-108% FTP

Highest you can hold for all four.

RECOVERY2 minTarget: 48.5-51.5% FTP

Easy.

COOLDOWN10 minTarget: 48.5-51.5% FTP

RELATED WORKOUTS

  • CyclingThresholdDifficulty 4 of 5 — Very hard

    Seiler 4 × 16

    4 × 16 min at the highest sustainable power, 2–3 min easy

    1 h 40Inspired by Stephen Seiler
    Save Send

NOT HERE? DESCRIBE IT.

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