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Cycling · VO2max

RØNNESTAD 30/15S

3 × 13 × (30 s hard / 15 s easy), 3 min between sets

Time · 1 hDifficulty · Difficulty 4 of 5 — Very hardVery hardInspired by · Bent Rønnestad

THE STORY

From research by Bent Rønnestad and colleagues: the short-interval group rode 3 series of 13 × 30 seconds hard with 15 seconds easy, and 3 minutes between series — and improved more than a group doing 4 × 5-minute intervals.

Sources

  1. Short intervals induce superior training adaptations compared with long intervals in cyclists - an effort-matched approach — Scandinavian Journal of Medicine & Science in Sports (PubMed), 2015

WHAT IT TRAINS

A lot of time near VO2max: the 15-second recoveries are too short for oxygen uptake to fall.

WHO IT'S FOR

Trained cyclists. The second and third sets are where the work happens.

HOW TO DO IT

  1. 01Warm up 15 minutes.
  2. 0213 × (30 seconds hard, about 120–130% FTP; 15 seconds easy).
  3. 033 minutes easy. Repeat for 3 sets.
  4. 04Cool down 10 minutes.

SCALED VERSION

2 sets of 10 × 30/15.

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 00min 15s

Rønnestad 30/15s

3 × 13 × (30 s hard / 15 s easy), 3 min between sets · Inspired by Bent Rønnestad. · Fit File Forge Workout Library: www.fitfileforge.com/workouts/library/ronnestad-30-15s

WARMUP15 minTarget: 50-75% FTP

Building from 50% to 75% FTP.

13×Repeat

INTERVAL30 secTarget: 120-130% FTP

RECOVERY15 secTarget: 48.5-51.5% FTP

Easy.

RECOVERY3 minTarget: 48.5-51.5% FTP

Easy.

13×Repeat

INTERVAL30 secTarget: 120-130% FTP

RECOVERY15 secTarget: 48.5-51.5% FTP

Easy.

RECOVERY3 minTarget: 48.5-51.5% FTP

Easy.

13×Repeat

INTERVAL30 secTarget: 120-130% FTP

RECOVERY15 secTarget: 48.5-51.5% FTP

Easy.

COOLDOWN10 minTarget: 48.5-51.5% FTP

RELATED WORKOUTS

  • CyclingVO2maxDifficulty 4 of 5 — Very hard

    40/20s

    2–3 × 10 × (40 s hard / 20 s easy), 5 min between

    1 h 05
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  • CyclingVO2maxDifficulty 3 of 5 — Hard

    15/15s

    3 × 10 min of 15 s hard / 15 s easy

    1 h 05
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