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RunVO2max

Billat 30/30s

16–20 × (30 s at vVO2max / 30 s easy)

Time
43 min
Hard
9:00
in zones 4–5
Difficulty
HardDifficulty 3 of 5 — Hard
Inspired by
Véronique Billat

What we typed

Warm up 15 min easy. 18 × (30 s fast at about 3K effort, 30 s easy jog). Note: 16–20 reps. Cool down 10 min easy.

Fit File Forge built the steps below from these words — the same steps your watch gets.

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The session

4 steps

Warm up

easy

15 minZ2
18×30 s

Rep

fast at about 3K effort; 16–20 reps

30 secZ5

Jog

30 secZ1

Cool down

easy

10 minZ1

Targets

Set by race effort. Your paces follow from your threshold pace — about what you could race for an hour.

3K effort

Save it and race efforts become your own paces, from your profile or your Garmin training. Without them every rep keeps its effort cue.

Scaled version

Start with 10 × 30/30 and add two each week.

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About this session

The story

From Véronique Billat's research: runners alternating 30 seconds at the velocity associated with VO2max and 30 seconds at half that speed spent more time at VO2max than in a continuous run.

What it trains

Time at or near VO2max without the misery of long intervals — the short recoveries keep oxygen uptake high.

Who it's for

Everyone from new 5K runners to marathoners. 'Fast' is roughly 3K effort, the recovery a gentle jog.

Sources 1
  1. Intermittent runs at the velocity associated with maximal oxygen uptake enables subjects to remain at maximal oxygen uptake for a longer time than intense but submaximal runs — European Journal of Applied Physiology (PubMed), 2000

I've been using the AI Training Coach from day 1 for marathon prep and have found it to be a huge step up from ChatGPT/Gemini — I couldn't be happier.

Dave F.Marathon athlete

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