We’re excited to share an important update: the story and science behind the training method that forms the foundation of the Myworkout app is now available to readers worldwide.
The Norwegian 4x4 Method: Science, History and Practice from its Creators, written by professors Jan Helgerud and Jan Hoff together with Øystein Lie, offers a rare inside look into the method that has influenced both elite sports and modern preventive medicine.
For the first time, international readers can dive into the story of how a simple idea — four intervals of four minutes — became one of the most effective ways to improve both health and performance.
This book tells the story of two researchers determined to understand what truly improves the heart and body. Their findings led to what we now know as the Norwegian 4x4 method.
The method has shaped the training of:
But perhaps the most meaningful impact came outside elite sports. Over the past two decades, Helgerud and Hoff have shown how high-intensity training can improve health and longevity for patients with heart disease, stroke, COPD, MS, and several lifestyle diseases.
This research is the foundation Myworkout is built on — and the reason we believe exercise can be a powerful form of medicine.
The Kindle edition brings together:
A clear explanation of why high-intensity intervals — especially the 4x4 protocol — are so effective for improving VO₂max and overall health.
How two professors from Trondheim, Norway, developed a method that transformed both athletic training and medical rehabilitation.
A 12-week endurance and strength program suitable for everyone — from beginners and patients to elite athletes.
This is more than a training guide. It’s a piece of modern exercise science history.
Our app is built directly on the research and methods described in this book.
With Myworkout, you can measure your VO₂max and biological age with a margin of error of just 4.5%— and 4x4 remains at the heart of our approach in the app, in clinics, and in our training centers.
Having the book available on Kindle means more people can understand the science behind what we do, and why it works so well.
Ready to dive into the history and science behind the Norwegian 4x4 method?
👉 Get The Norwegian 4x4 Method on Kindle
And if you want to experience the method in practice:
👉 Download the Myworkout 4x4 App
Track your 4x4 intervals, measure your VO₂max, and discover your biological age — based on 30+ years of leading research.
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