4x4 Norwegian Intervals

Four 4-minute hard efforts at ~90-95% HRmax with 3-minute easy recoveries. A strongly evidenced VO2max stimulus. High intensity; warm up fully. Default 40 min.

Grade inherited from the evidence blocks this routine implements. Duration is a starting point (do more or less); the app just tells you where you land against the evidence-based dose.

1
Jog (Moderate)
10 min progressive warm-up
Finish the warm-up feeling ready to work.
2
4x4 Run Block (Norwegian Intervals)
4 x 4 min hard @ RPE 8-9, 3 min easy jog between
Substitute bike, rower, or treadmill to reduce impact.
3
Easy Run (Zone 2)
6 min easy cool-down
Keep moving until breathing normalizes.

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Opens the builder on Cardio & Endurance, where you can select sessions and add them to your week.

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