VO₂ Max Training: What It Is, What It Isn’t, and How to Actually Do It Right

(Including the Norwegian 4×4)

VO₂ max training has become a buzzword.

Everyone wants:
• A higher VO₂ max
• Shorter workouts
• Faster results

So people smash themselves with “hard intervals” and assume the job is done.

But VO₂ max adaptations don’t come from suffering.
They come from spending enough time at the right physiological intensity.


What VO₂ Max Training Is Actually Targeting

VO₂ max represents the maximum rate at which your body can deliver, utilize, and recycle oxygen during intense exercise.

Training it improves:
• Cardiac output (stroke volume)
• Oxygen delivery
• Mitochondrial density
• Aerobic power ceiling

But here’s the key:

VO₂ max training is about time at high oxygen uptake, not peak effort.

If you spike HR quickly and then fade, you’re not accumulating useful stimulus — you’re just accumulating fatigue.

And because it's about time at high oxygen uptake, if you do the exact same volume every week (ie only 4x4), then you're failing to increase the time at high oxygen uptake, and thus you're failing to impact VO2 max more than you already have adapted to.


Why Most “Hard Intervals” Miss the Mark

Common mistakes:
• Starting too hard - poor pacing
• Letting HR spike immediately
• Not recovering enough between intervals

The result?
• Very short time near VO₂ max
• Massive sympathetic load
• Poor repeatability
• Long recovery cost

Hard ≠ effective.


The Norwegian 4×4: Why It Works (When Done Correctly)

The classic structure:
• 4 minutes hard
• 3 minutes easy
• Repeat 4 times

But the execution matters more than the format.  It's not magic


How to Execute the Norwegian 4×4 Properly

Intensity target

During each 4-minute interval:

Workload should be hard but sustainable.

HR should gradually rise into ~90–95% of max HR
You should reach the Morpheus red zone, not blast into it.  It may not reach there during the first rep.

If HR spikes in the first 60–90 seconds, you started too hard.


Workload Pacing

Think:
• Strong
• Controlled
• Sustainable across all 4 intervals

Interval 1 should feel almost too easy.
Interval 4 should feel hard — but still controlled.

If interval 4 collapses, interval 1 was too aggressive.


Recovery intervals

The 3-minute recovery is not passive suffering.

Goal:
• Allow HR to come down
• Restore enough parasympathetic control to repeat quality work

If HR stays excessively elevated between reps:
• The previous interval was too hard
• Or overall recovery state is poor


Total goal

The win is:
• Accumulating time near VO₂ max
• With minimal drift and collapse

Not:
• Redlining
• Gasping
• Needing to lie down afterward


How Often Should You Do VO₂ Max Work?

For most people:
• 1–2 sessions per week max
• Only when recovery metrics support it
• Never layered on top of excessive volume

VO₂ max work is high return, high cost.

It needs:
• Adequate aerobic base
• Good sleep
• Proper fueling
• Smart spacing


Why Recovery Context Matters

VO₂ max sessions place a large demand on:
• The sympathetic nervous system
• Cardiac output
• Glycolytic and aerobic systems

If recovery is already compromised:
• HR rises faster
• HRV may be suppressed
• Quality drops
• Injury risk increases

This is where data matters.

Because VO₂ max training done poorly doesn’t just fail to improve VO₂ max —
it actively interferes with adaptation.  That's why you should only do this type of workout on a high recovery score day.


The Big Takeaway

VO₂ max training is not about:
• Suffering
• Maximal pace
• Destroying yourself

It’s about:
• Precision
• Repeatability
• Time at the right physiological intensity

The Norwegian 4×4 works because it respects the system, not because it's some magic formula.

When you respect the system, it adapts.
When you fight it, it just defends itself.