The 4x4 VO₂ Max Booster

Workout - The 4x4 VO₂ Max Booster

• 15min @ 6'30''/km
• 4 lots of:
  • 4min @ 4'00''/km
  • 4min rest
• 12min @ 6'30''/km

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Intro: Peter Attia MD’s breakdown of cardiovascular training is worth your time. Here’s what you need so you can start the workouts right away. The full video has more depth.

Key points

• Picture cardiovascular development as a triangle. Zone 2 low-intensity work is the foundation; VO2 max high-intensity work sits at the top. Most training follows an 80% Zone 2 / 20% VO2 max ratio (some elite athletes use 90/10).
• At 4–5 hours of training per week, that’s roughly 3.5 hours of Zone 2 and 0.5–1 hour of VO2 max intervals.
• Zone 2 means 30–60 minute blocks at a pace or perceived effort that’s easily maintainable. Conversation should still flow. Spread sessions across 2–4 days, with individual workouts of 30–45 minutes.
• VO2 max training works best with 3–8 minute hard efforts (for example, 4 minutes fast followed by 4 minutes recovery) on hills, a bike, treadmill, rowing machine, or stair climber. Add a 10-minute warm-up before the hard section.
• Showing up regularly matters more than crushing one epic session. Target at least 30 continuous minutes of Zone 2 per session.

Workout example (weekly plan)

1. Monday: 90 minutes of lower-body strength and stability (skip if needed).
2. Tuesday: 45–60 minutes of Zone 2 (cycling, running, or easy treadmill), then 30 minutes of stability work.
3. Wednesday: 90 minutes of upper-body strength and stability.
4. Thursday: Repeat Tuesday’s Zone 2 session.
5. Friday: Repeat Monday’s strength routine.
6. Saturday: 45–60 minutes of Zone 2 in the morning; add upper-body strength in the afternoon.
7. Sunday: Start with 30 minutes of Zone 2, then VO2 max repeats. For example, 4 minutes hard uphill (or hard bike effort) alternated with 4 minutes easy recovery, 4–6 times.

Short on time? Two separate 30-minute Zone 2 blocks on different days, or one 30-minute session paired with a short VO2 max burst.

Practical tips

• Use a HR monitor or RPE to stay in Zone 2; that’s often more reliable than HR numbers alone.
• Pick a VO2 max activity where you can push for 3+ minutes (uphill repeats, assault bike, or rower).
• Allow 10 minutes of warm-up before the hard effort. Aim for roughly 1 hour of intense work per week.
• Log everything in the Pacing app and tune target speeds to your HR zones.

Closing note: Try this 80/20 cardio framework this week and adjust session lengths to your schedule.

References

• How to train your cardiovascular fitness | Peter Attia - YouTube (YouTube Video)