The Norwegian 4x4: The Best HIIT Workout to Boost Your VO2 Max and Turn Back Time

What it is, why it's awesome, and how I do it

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Once a week, my wife watches me ride what I call the Norwegian rollercoaster.

It involves a highly beneficial HIIT-style workout and a rollercoaster of emotions. 

Excitement. Dread. Acceptance. “I can do this”. Hope. “No I can’t.” Misery. Relief. Despair. And finally, bliss.

I hate it and love it so much.

Here’s what it is, why I do it, and how to get started today:

What is the Norwegian rollercoaster?

The Norwegian rollercoaster refers to the up-and-down behavior of my heart rate and mental state before, during, and after my once-weekly HIIT workout.

HIIT stands for high-intensity interval training. It’s a type of workout with alternating periods of high-intensity exertion followed by low-intensity recovery or rest.

There’s a whole spectrum of different HIIT-style workouts with varying interval durations and numbers of rounds. The specific protocol I use is called the Norwegian 4x4, hence the name of my rollercoaster.

It’s been gaining popularity in fitness circles around the internet thanks to big-name experts in longevity like Dr. Peter Attia, Dr. Rhonda Patrick, and Andrew Huberman (let’s ignore his questionable morals for this post).

Here’s what it looks like at a high level:

  • 4 min of high-intensity exertion

  • 3 min of rest

  • Repeat for a total of 4 rounds

I won’t lie. It’s a bear of a workout.

But it’s 1000% worth it (that’s not a typo).

Why You Need to Consider Hopping on the Ride

Before last year, VO2 max was a term that I knew existed but wouldn’t have been able to define. Now it’s a regular part of my vocabulary.

VO2 max is how fast your body can turn the oxygen from your blood into energy. It’s an indicator of your overall cardiorespiratory fitness. The higher your VO2 max, the higher your fitness level, and the more “in-shape” you are.

A good VO2 max should be important to you because, quantitatively:

  • It’s strongly correlated with longevity (i.e. dying later)

  • A higher VO2 max could lead to a 50% reduction in all-cause mortality over a 10-year span

  • After 2 years of consistent practice, a 50-year-old heart can structurally rejuvenate to one that looks up to 20 years younger

And qualitatively:

  • You feel phenomenal

  • It’s a massive confidence boost

  • You get in the best shape of your life

The supporting data shows that VO2 max continues to emerge as a critical indicator for living a long, healthy, happy life. Something I’m very interested in.

If you want to take a deeper dive into the topic, I previously wrote an article that does just that. For this article, I purposefully left out some details to keep the focus on the workout and not the science.

Now, if you want to improve your VO2 max, there are two things you need to do:

  1. Zone 2 cardio training

  2. High-intensity cardio training

The focus here is on the high-intensity portion, and the Norwegian 4x4 is the most effective high-intensity protocol to help increase your VO2 max.

Step-by-Step How to Do the Workout

Since starting my Norwegian 4x4 ritual, I’ve learned the ins and outs of how to navigate the workout.

Here’s the full breakdown.

1. Pick your day

My weekly routine is structured so that I have 3 days of strength training, 3 days of zone 2 cardio, and 1 day of Norwegian 4x4. 

Saturday is my go-to.

Any day works. Choose what’s best for your schedule.

2. Pick your poison

I imagine any form of cardio works, but my two favorites are:

  • Stationary bike

  • Running (treadmill or outside)

On rare occasions, I’ll do the rowing machine, but that’s if I really want to punish myself.

3. Pre-Workout Prep

The meat of the workout takes about 30 minutes in total.

Adding in some time for a warm-up and cooldown, I’d make sure to block off 40 minutes for the whole thing.

A few things I have ready before I start:

  • Sweat rag

  • Full water bottle / electrolytes

  • Airpods with some hype music

  • Apple Watch to track my time and heart rate zones

Sometimes if I’m on the bike, I’ll queue up a TV show or movie to watch to make the time pass faster.

4. Warm-up

I like to start with a dynamic warm-up.

Most often, I’ll do a 3-minute low-intensity interval as my warm-up before rolling right into the rest of the workout.

There’s lots of room for variation in your warm-up. It should be tailored to whatever you feel you need. Don’t stress too much about the specifics.

Mainly, just get your body moving and blood pumpin’.

5. High-intensity interval for 4 minutes

The goal is NOT to push yourself as hard as possible for 4 minutes.

I did this my first few workouts and wanted to die.

Instead, you want to exert yourself hard enough to increase your heart rate to 85–95% of your max then hold it there. Once it’s in the target range, it takes a little less effort to maintain.

There’s a key difference in that, trust me.

If you’re doing it right, you should be teetering between Zone 4 and Zone 5 (which I monitor on my Apple Watch).

The 4 minutes feel long. You will be huffing and puffing. By design, it’s supposed to be a challenge to push your limits.

Music helps a ton.

6. Rest for 3 minutes

The goal is to drop your heart rate down to Zone 1 before your next high-intensity interval.

When on the bike, I drop the resistance dramatically while continuing to pedal lightly.

When running, I slow down to a walk.

Whatever you do, savor the rest period because the next high-intensity one comes back around quickly. Too quickly…

7. Alternate for 4 total rounds

That’s it.

High then rest. Repeat 4x.

8. Cooldown

For me, the workout is over after I’ve completed my fourth high-intensity interval.

I cheat and use the final rest / low-intensity interval as the bulk of my cooldown.

When that’s over, I collapse onto the floor to do some static stretching while basking in the glory of being done.

There is no better feeling than laying there on the floor, drenched in sweat, staring up at the heavens, panting like a dog, with a surge of feel-good chemicals circulating throughout the body.

The rollercoaster ends on one hell of a high note.

If you make it here, it’s something to be proud of. You kicked ass and did something insanely hard but super good for your health.

A Few Other Things to Note

  • I am not a doctor. Definitely consult your doctor before trying something new.

  • User experience may vary. If brand new to the Norwegian 4x4 or HIIT in general, don’t immediately start with 4-minute high-intensity and 3-minute low-intensity intervals. Start small and build up.

  • You will be amazed after a short period of time at how fast your body adapts. It takes more effort to reach the higher zones when your heart gets stronger.

  • If somehow the workout gets too easy, you can continue to progress to a 4x6 protocol (6 total rounds instead of 4).

  • Don’t skip the warm-up (I’ve done it and it’s not fun).

  • You might get really hungry after your workout. Voracious is a term I would use to describe myself some days.

And that’s a wrap.

Considering that it’s Saturday today, I’m soon to be off riding the Norwegian rollercoaster.

Hope you’ll give it a try. For health.



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