N4x4 App
Norwegian 4x4 Protocol to increase your VO2 Max for endurance, health and longevity
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Boost Your Fitness with N4x4 – The Proven Way to Improve VO2 Max
"VO2 Max is the single greatest predictor of lifespan." — Dr. Peter Attia
The Norwegian 4x4 is the best High Intensity Interval Training (HIIT) protocol to increase your VO2 Max. It has nothing to do with cars. :-)
The N4x4 app guides you through the gold-standard Norwegian 4x4 interval training. No fluff — just a simple, powerful tool to help you increase your VO2 Max, the key metric for longevity.
The benefits of the Norwegian 4x4 protocol has been promoted by experts like Dr. Rhonda Patrick (no association with N4x4), who explains the protocol, in this 90 second clip:
How it works
The Norwegian 4x4 is a high intensity interval training (HIIT) protocol with the following steps:
- 5-minute warm-up
- 4x rounds of:
- 4 minutes of intense cardio at 85-95% of your Maximum Heart Rate (MHR)
- 3 minutes of light recovery
Recommended Exercises for N4x4
In general you can do any exercise that can get your heart rate up to the required level. It is easier to use stationary equipment to keep the effort level constant. But perfect can be the enemy of good and good is better than nothing. If you don't have stationary gym equipment, just find a place where you can run with as little as possibile variability. A flat or steady incline run will work just fine. Here are some other exercise ideas:
- Running (treadmill makes it easier to control the intesity)
- Cycling (stationary is easier for intensity control)
- Swimming
- Rowing
- Walking - For beginners, start with lighter exercises like brisk walking, and gradually increase intensity as your fitness improves
Do I need a heart rate monitor?
You can do the Norwegian 4x4 protocol without a heart rate monitor. Just push yourself as hard as you can sustain for 4 minutes at a time. If you push yourself hard enough, you should not be able to speak during the intense intervals. However, if you do have a heart rate monitor you can get more geeky, see the next section.
How to Calculate Your Maximum Heart Rate
To determine your maximum heart rate (MHR), use the following formula:
- Subtract your age from 220 (e.g., if you're 40 years old, 220 - 40 = 180). Your MHR is 180 beats per minute (BPM).
- For Norwegian 4x4, aim for 85-95% of your MHR during the 4-minute high-intensity intervals. In this example, that would be between 153 and 171 BPM.
- During the recovery periods, your heart rate should drop to around 60-70% of your MHR (e.g., 108-126 BPM).
Download N4x4 now and make the best investment in your health for only 30 minutes per week.