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 should know so you can start implementing these workouts right away. The full video contains much more depth if you want to explore further.

Key Points:

• Picture your cardiovascular development as a triangle. Zone 2 low-intensity work forms the foundation, while VO₂ max high-intensity work sits at the top. Most training should follow an 80% Zone 2 / 20% VO₂ max ratio (though some elite athletes work with 90/10).
• When training 4–5 hours weekly, dedicate about 3.5 hours to steady-state Zone 2 and roughly 0.5–1 hour to VO₂ max intervals.
• Zone 2 work requires 30–60 minute blocks at a pace or perceived effort that’s easily maintainable—conversation should still come naturally. Spread these sessions across 2–4 days to keep individual workouts between 30–45 minutes.
• VO₂ max training works best with 3–8 minute hard efforts (like 4 minutes fast followed by 4 minutes recovery) performed on hills, a bike, treadmill, rowing machine, or stair climber. Plan for a 10-minute warm-up before pushing into the hard section.
• What matters most is showing up regularly rather 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 (can skip if needed).
2. Tuesday: 45–60 minutes of Zone 2 (cycling, running, or easy treadmill work), followed by 30 minutes of stability training.
3. Wednesday: 90 minutes of upper-body strength and stability work.
4. Thursday: Repeat the Tuesday Zone 2 session.
5. Friday: Repeat the Monday 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 move into VO₂ max repeats—for example, 4 minutes hard uphill (or intense bike effort) alternating with 4 minutes easy recovery, done 4–6 times through.

Don’t have much time? Pair two separate 30-minute Zone 2 blocks on different days, or do one 30-minute session paired with a short VO₂ max burst.

Practical Tips:

• Rely on a heart-rate monitor or your rate of perceived exertion to stay properly in Zone 2; this approach tends to be more accurate than heart-rate numbers alone.
• Pick a VO₂ max activity where you can push hard for 3 minutes or longer (uphill repeats, assault bike, or rowing machine work well).
• Leave 10 minutes for warm-up before beginning your hard effort; the goal is roughly 1 hour of intense work spread across your week.
• Log everything in the Pacing app and fine-tune your target speeds based on your own heart-rate zones.

Closing Note: Give this 80/20 cardio framework a shot this week, adjust the session lengths to fit what works for you, and you’ll notice your aerobic capacity improve. The Pacing app lets you dial in your own threshold paces—go put in the work and see what happens.

References

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