VO₂ Max Booster 4x4

Workout - VO₂ Max Booster 4x4

• 10min @ 6'30''/km
• 4min @ 3'50''/km
• 4min rest
• 4min @ 3'50''/km
• 4min rest
• 4min @ 3'50''/km
• 4min rest
• 4min @ 3'50''/km
• 4min rest
• 10min @ 6'30''/km

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Here’s an overview of How often should you be doing Zone 5 training? featuring Peter Attia MD. The workout is below so you can start practicing it. Watch the original video for context and nuance.

Key points:

• High-intensity Zone 5 work drives gains in VO₂ max, mitochondrial function, and glycolytic capacity. All tied to longevity.
• Too much high-intensity work becomes unsustainable. Pair it with steady Zone 2 (low-intensity) sessions for balance.
• Add one session per week: either an extended Zone 2 effort or a focused VO₂ max interval block like the “4-by-4” protocol.
• Schedule high-intensity intervals after Zone 2 sessions, not before, so elevated lactate doesn’t suppress fat oxidation.

Workout example (the 4-by-4 protocol):

1. 10 to 15 min Zone 2 warm-up (easy effort, under 3 W/kg).
2. Push hard for 4 min into Zone 5 (roughly 90 to 95% max HR or 5 to 6 W/kg).
3. Drop back for 4 min of easy Zone 2 recovery.
4. Repeat 5 to 6 times. Total workout about 1 hour with warm-up and cool-down.

Running 4 to 5 Zone 2 sessions weekly (60 to 90 min each)? Slot this interval session in when your calendar allows. Adjust repeat count to your schedule.

Closing note: try the 4-by-4 once this week and see how your body responds. Adjust duration, reps, or intensity in the Pacing app to your fitness.

References

• How often should you be doing Zone 5 training? | Iñigo San-Millán, Ph.D. & Peter Attia, M.D. - YouTube (YouTube Video)